Low-density and high-transmittance display glass plate and preparation method thereof

Abstract

The present invention discloses a low-density and high-transmittance display glass plate and a preparation method thereof, which comprises the following components in weight percentage based on oxides: SiO2 57.1-65.3%, Al2O3 14.2-22.7%, B2O3 0.01-4.3%, ZrO2 0-1%, P2O5 0.0001-0.05%, MoO3 0-0.01%, Fe2O3 0-0.3%, SnO2+SnO 0.1-0.3% and RO 13-21%; wherein RO is at least one of MgO, CaO, SrO and BaO. The glass plate prepared by the present invention has high visible light transmittance and high ultraviolet band (308nm) transmittance, and has a relatively low density, which can effectively solve the problem of low yield caused by defects such as deformation (BOW shape) caused by excessive panel area.

Description

Technical Field

[0001] The present invention relates to the technical field of glass production, and in particular to a low-density and high-transmittance display glass plate and a preparation method thereof. Background Art

[0002] With the rapid development of display technology and 5G technology, home and commercial display terminals have grown from 55 inches to the current 65 inches, 75 inches and even larger sizes. Glass plates, as the most important and critical component material for displays, have also made great progress, from the initial G3 products to the current G5, G6, G8.5, G10.5 and G11 products. However, this also brings great challenges to production. Due to the difference in the self-weight and performance of glass, plate deformation (also known as BOW shape) occurs during the production of large-size display devices, which reduces product yield and increases production costs.

[0003] With the gradual application of high-performance display technology and flexible display technology, especially in the production of flexible display devices, glass as a carrier needs to adopt laser curing and peeling technology. In order to ensure the efficiency and accuracy of laser curing and peeling, 308nm laser is usually used in the actual process, and its 308nm transmittance is required to be higher than 70%. At the same time, the uniformity of glass transmittance is required to be high. The uneven transmittance between and within glass sheets will greatly increase the panel processing cost.

[0004] The glass plate for display is alkali-free aluminum borosilicate glass, which has high melting and clarification temperatures and is difficult to process. The melting and clarification technology of glass is the most critical step related to the inherent defects of glass. In order to improve the melting quality of glass, simply increasing the melting temperature of the kiln will increase the erosion of the refractory materials of the melting furnace by the glass liquid, which is likely to increase glass defects (unmelted materials, bubbles, etc.) and greatly shorten the service life of the melting furnace. In addition, due to the particularity of the manufacturing process of flexible display devices, it has very high requirements for the transmittance at 308nm. Therefore, in order to make the performance of the produced glass plates meet the requirements of downstream customers and at the same time achieve better glass production efficiency, it is necessary to further develop suitable melting processes and matching glass formulas. Summary of the invention

[0005] The technical problem to be solved by the present invention is: to overcome the shortcomings of the prior art and provide a low-density and high-transmittance glass plate for display and a preparation method thereof. The prepared glass plate has high visible light transmittance and high ultraviolet band (308nm) transmittance, and can not only be used as a glass substrate for display, but also can be used as a carrier in the preparation process of high-performance display devices. Especially when manufacturing large-size panels, it can effectively solve the problem of low yield caused by defects such as deformation (BOW shape) caused by excessive panel area.

[0006] The technical solution of the present invention is:

[0007] On the one hand, the present invention provides a low-density and high-transmittance glass plate for display, which, based on oxides, includes the following components in weight percentage: SiO2 57.1-65.3%, Al2O3 14.2-22.7%, B2O3 0.01-4.3%, ZrO2 0.01-1%, P2O5 0.0001-0.05%, MoO3 0.0002-0.01%, Fe2O3 0.005-0.3%, SnO2 0.1-0.2%, SnO 0.01-0.1% and RO 13-21%; wherein RO is at least one of MgO, CaO, SrO and BaO.

[0008] The presence of Fe2O3 in the raw materials can improve the quality and efficiency of glass melting, but too high a content will color the glass and reduce the glass transmittance, so the total amount of Fe2O3 in the glass needs to be controlled. Adding SnO2 and SnO at the same time can improve the clarification effect and the addition amount is controlled at 0.1-0.3%.

[0009] P2O5 in the raw materials can lower the melting temperature of the glass. Its viscosity activation energy is close to that of B2O3. At the same time, P2O5 enters the glass structure to form [PO4], which has an oxygen with a double bond. The phosphorus oxygen tetrahedron with a double bond is an asymmetric center, which can reduce the viscosity of the glass, thereby reducing the high-temperature characteristic viscosity point of the glass, which is beneficial to the melting of the glass. In particular, P2O5 can also improve the ultraviolet transmittance of the glass, but too high a content will easily cause the glass to phase separate. Therefore, the content of P2O5 is 0.0001-0.05%, and the preferred content is 0.0002-0.03%.

[0010] MoO3 in the raw material can reduce the melting temperature of glass and the surface tension of glass. MoO3 is mostly present in molten glass as Mo 6+ It exists in the form of ions and will not cause the glass to color under an oxidizing atmosphere, but can cause the glass to color under a strong reducing atmosphere. Considering that the melting atmosphere in the preparation method of the present invention is a reducing atmosphere, in order to ensure the quality of glass melting, the MoO3 content is limited to 0.0002-0.01%, and the preferred content is 0.00005-0.004%.

[0011] On the other hand, the present invention also provides a method for preparing the above-mentioned low-density and high-transmittance display glass plate, wherein the components are mixed evenly, and then put into a kiln for melting to obtain a glass liquid, which is clarified for a second time in a clarification process, and then enters a molding process for molding. The molded glass plate is annealed and cooled before being cut, and finally ground, polished, cleaned, dried, and packaged.

[0012] Preferably, the kiln includes a connected melting zone and a clarification and homogenization device, the melting zone is a closed area consisting of a front wall, side walls, a rear wall, a furnace bottom and a vaulted roof, a hanging wall is arranged on the vaulted roof in the melting zone, dividing the melting zone into a first chamber and a second chamber; a feeding port is arranged on the front wall of the melting zone, a discharging port is arranged on the rear wall, and several pairs of burners are respectively arranged on the side walls at the first chamber and the second chamber, and the several pairs of burners are arranged at intervals along the length direction of the kiln; several fluxing electrodes are respectively arranged on the furnace bottoms of the first chamber and the second chamber; several upper thermocouples are arranged at intervals on the vaulted roofs of the first chamber and the second chamber along the length direction of the kiln, and lower thermocouples are arranged at intervals on the furnace bottom along the length direction of the kiln.

[0013] Preferably, the melting zone is rectangular, and its length-to-width ratio is 3-3.5:1; when the height of the melting zone is set to G, the distance between the bottom edge of the feeding port and the glass liquid surface is greater than 0.2G.

[0014] Preferably, the burners are arranged in 5-8 pairs, the number of burners is preferably an even number, and the height from the glass liquid surface is greater than 0.3G; the burners adopt natural gas-oxygen and natural gas-air combustion. Since the calorific value generated by natural gas-oxygen combustion is higher than that of natural gas-air combustion, there is a certain temperature gradient above the glass liquid in the kiln. Therefore, the glass liquid will undergo forced convection flipping in the kiln, so that the glass body is heated and homogenized in the kiln; preferably, according to the flow meter, the ratio of natural gas-oxygen burners to natural gas-air burners is 3:1; when the burner adopts natural gas-oxygen, the ratio of natural gas to oxygen is 1:1.9, and when the burner adopts natural gas-air, it is 1:0.3.

[0015] Since there is Fe2O3 in the raw materials, under the high temperature condition in the kiln, Fe2O3 is divided into Fe 2+ Ions and high-valent Fe 3+ The ion exists in two states, Fe 3+ There are three absorption bands at 380nm, 420nm and 435nm respectively. 2+ The absorption band absorbs infrared rays at 1050nm. In order to ensure that the glass has a high transmittance at 308nm, the atmosphere in the kiln needs to be in a slightly reducing atmosphere.

[0016] Preferably, the fluxing electrodes are one or both of molybdenum-zirconium electrodes and tin electrodes. When both fluxing electrodes are used at the same time, the number of molybdenum-zirconium electrodes is greater than the number of tin electrodes.

[0017] Preferably, among the heat provided by the fluxing electrode and the burner, the heat provided by the fluxing electrode accounts for more than 70%.

[0018] Preferably, when the length of the melting zone is set to Cz, a fluxing electrode is arranged on the center line of the length direction of the furnace bottom of the first chamber at a position 0.03Cz-0.08Cz away from the feeding port. This is because there are more raw materials at the feeding port, so arranging a fluxing electrode here can ensure a higher melting efficiency of the raw materials here; behind the fluxing electrode, a plurality of rows of fluxing electrodes are arranged at intervals along the width direction of the melting zone, and the distance between the fluxing electrodes close to the side walls on both sides and the side walls is greater than 600mm, and further preferably, the distance is greater than 800mm, so as to prevent the fluxing electrodes from being too close to the side walls and aggravating the glass Corrosion of refractory materials; on the furnace bottom of the second chamber, two rows of fluxing electrodes are symmetrically arranged at a position 0.05Cz away from the discharge port; the height of the fluxing electrodes in the first chamber is greater than 100mm, and further preferably, the height of the fluxing electrodes in the first chamber is 200-400mm to ensure the melting effect of the middle and bottom of the molten glass, and the height of the fluxing electrodes in the second chamber is 400-800mm higher than that of the fluxing electrodes in the first chamber, because the thickness of the molten glass liquid in the second chamber is thinner than that in the first chamber, so the fluxing electrodes in the second chamber play a role of heat preservation on the one hand, and a role of preliminary degassing and clarification on the other hand.

[0019] According to the working principle of the fluxing electrode, the greater the surface current density of the fluxing electrode, the greater the Joule heat generated and the better the fluxing effect. However, in order to obtain high-quality glass and a longer service life of the fluxing electrode, a lower surface current density should be used. Therefore, preferably, the surface current density of the fluxing electrode is 0.5-1.6A / cm 2 , the total surface current density of the fluxing electrodes in the first chamber accounts for 70-90% of the total surface current density of all fluxing electrodes, and the ratio of the surface current density of the two rows of fluxing electrodes close to the second chamber to the total surface current density of all fluxing electrodes is greater than 30%. The surface current density of the fluxing electrodes is limited in order to increase the fluidity of the molten glass liquid, eliminate the stagnant parts caused by the immobile layer and non-flow phenomenon of the molten glass liquid in the melting zone, and use the temperature gradient to form convection in the melting zone to achieve an ideal state, so as to improve the quality of the glass liquid. However, when the surface current density of the fluxing electrodes is too large and the ratio of the surface current density of the two rows of fluxing electrodes close to the second chamber to the total surface current density of all fluxing electrodes is too small, the erosion of the kiln pool wall bricks and pool bottom bricks will increase, thereby increasing the probability of defects such as stones in the glass.

[0020] The temperature pattern in the melting zone should be set as follows: the temperature of the lower part of the glass liquid in the first chamber and the second chamber should be higher than the temperature of the upper part of the glass liquid, the temperature of the rear part of the first chamber should be higher than the temperature at the feeding port of the first chamber, and the temperature of the front part of the second chamber should be higher than the temperature at the discharging port. The heating temperatures of the first chamber and the second chamber can be set by those skilled in the art as long as the set temperatures can achieve the melting of the glass raw materials and the reaction temperature of the clarifier.

[0021] Preferably, the temperature of the glass liquid in the clarification and homogenization device is ≥1500°C, and the pressure of the clarification and homogenization device is adjusted according to the different glass components. If the pressure is too high, the clarification effect cannot be achieved, and if the pressure is too low, secondary bubbles are easily generated, which also affects the service life of the clarification and homogenization device. Therefore, the pressure is set to 0 to -1.5Mpa, and the preferred pressure is -0.2 to -0.7Mpa, which can minimize glass defects (bubbles, streaks). The melting zone and the clarification and homogenization device can be used together to better improve the quality of alkali-free glass. The clarification and homogenization device is provided with an exhaust hole, and the exhaust hole is connected to a vacuum pump through a vacuum pipeline. A pressure sensor is provided on the vacuum pipeline to ensure that the clarification and homogenization device is negative pressure. In order to ensure the best clarification effect, the height of the glass liquid level in the clarification and homogenization device is 1 / 2 to 2 / 3 of the height of the pipeline at the horizontal position. If the height of the glass liquid level is too high, it will not have a clarification effect.

[0022] Compared with the prior art, the present invention has the following beneficial effects:

[0023] The low-density, high-transmittance display glass plate prepared by the present invention has a thickness of less than 0.5 mm, preferably less than 0.3 mm, and a plate width of more than 1500 mm, preferably more than 2000 mm, and has the following advantages: 1) the glass plate has a relatively low density, relatively low viscosity, is easy to clarify, and has few defects; 2) the glass plate has a high visible light transmittance and a high ultraviolet band (308 nm) transmittance. The glass plate prepared by the raw material composition and method of the present invention can not only be used as a display glass substrate, but also can be used as a carrier in the preparation process of high-performance display devices, especially in the manufacture of large-size panels, which can effectively solve the problem of low yield caused by defects such as deformation (BOW shape) caused by excessive panel area. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 It is a top view of the melting zone and clarification homogenization device of the present invention.

[0025] Figure 2 It is a side view of the melting zone and clarification homogenization device of the present invention.

[0026] In the figure, 1, melting zone; 101, front wall; 102, side wall; 103, rear wall; 104, furnace bottom; 105, hanging wall; 106, feeding port; 107, discharging port; 108, first chamber; 109, second chamber; 2, burner; 3, flux electrode; 4, upper thermocouple; 5, lower thermocouple; 6, clarification and homogenization device; 7, glass liquid surface. DETAILED DESCRIPTION

[0027] In order to enable persons skilled in the art to better understand the technical solution of the present invention, the technical solution of the present invention will be clearly and completely described below in conjunction with the embodiments of the present invention.

[0028] The low-density and high-transmittance display glass plate of the present invention comprises the following components in weight percentage based on oxides: SiO2 57.1-65.3%, Al2O3 14.2-22.7%, B2O3 0.01-4.3%, ZrO2 0.01-1%, P2O5 0.0001-0.05%, MoO3 0.0002-0.01%, Fe2O3 0.005-0.3%, SnO2 0.1-0.2%, SnO 0.01-0.1% and RO 13-21%; wherein RO is at least one of MgO, CaO, SrO and BaO.

[0029] In the present invention, the preparation method of the low-density and high-transmittance display glass plate is as follows: the components are mixed evenly, and then put into a kiln for melting to obtain a glass liquid, which is clarified twice in a clarification process, and then enters a molding process for molding. The molded glass plate is annealed and cooled before cutting, and finally ground, polished, cleaned, dried, and packaged.

[0030] Among them, Figure 1-2 As shown, the furnace includes a connected melting zone 1 and a clarification and homogenization device 6. The melting zone 1 is a closed area consisting of a front wall 101, a side wall 102, a rear wall 103, a furnace bottom 104 and a vaulted roof, and is generally rectangular, with a length and a width of 6.5 m and 2.1 m respectively. A hanging wall 105 is arranged on the vaulted roof in the melting zone 1, dividing the melting zone 1 into a first chamber 108 and a second chamber 109. Two feeding ports 106 are symmetrically arranged on the front wall 101 of the melting zone 1 along the center line of the length direction of the furnace. When the height of the melting zone 1 G=2.7 m, the bottom edge of the feeding port 106 is 7 m away from the glass liquid surface. 0.57m; a discharge port 107 is provided on the rear wall 103, five pairs of burners 2 are provided at the first chamber 108 on the side wall 102, and two pairs of burners 2 are provided at the second chamber 109, which are 0.83m above the glass liquid level 7, and the burners 2 are arranged at intervals along the length direction of the kiln; a plurality of fluxing electrodes 3 are respectively provided at the furnace bottom 104 of the first chamber 108 and the second chamber 109; a plurality of upper thermocouples 4 are arranged at intervals on the arched tops of the first chamber 108 and the second chamber 109 along the length direction of the kiln, and lower thermocouples 5 are arranged at intervals at the furnace bottom 104 along the length direction of the kiln.

[0031] In the present invention, the burner 2 uses natural gas-oxygen and natural gas-air for combustion. The fuel of the second and third pairs of burners 2 in the first chamber 108 is natural gas-air, and the remaining burners 2 all use natural gas-oxygen. According to the flow meter, the ratio of natural gas-oxygen burner 2 to natural gas-air burner 2 is 3:1. When the burner 2 uses natural gas-oxygen, the ratio of natural gas to oxygen is 1:1.9, and when the burner 2 uses natural gas-air, it is 1:0.3. The flux electrode 3 uses molybdenum-zirconium electrode and tin electrode, with 25 molybdenum-zirconium electrodes and 10 tin electrodes. The heat provided by the flux electrode 3 accounts for 75% of the total.

[0032] At the same time, if Figure 1 As shown, in the present invention, the length of the melting zone 1 is 6.5m, and a fluxing electrode 3 is arranged at a position 0.51m away from the feeding port 106 on the center line of the length direction of the furnace bottom 104 of the first chamber 108. Behind the fluxing electrode 3, 5 rows of fluxing electrodes 3 are arranged at intervals along the width direction of the melting zone 1, each row is composed of 6 fluxing electrodes 3, and the distance between the fluxing electrodes 3 close to the side walls 102 on both sides and the side walls 102 is 0.83m. On the furnace bottom 104 of the second chamber 109, 2 rows of fluxing electrodes 3 are symmetrically arranged at a position 0.325m away from the discharge port 107; the height of the fluxing electrode 3 in the first chamber 108 is 0.38m, and the height of the fluxing electrode 3 in the second chamber 109 is 0.43m higher than the fluxing electrode 3 in the first chamber 108.

[0033] The surface current density of the flux electrode 3 is 1.2A / cm 2 The total surface current density of the fluxing electrodes 3 in the first chamber 108 accounts for 80% of the total surface current density of all fluxing electrodes 3 , wherein the total surface current density of the fluxing electrodes 3 in the fourth and fifth columns accounts for 35% of the total surface current density of all fluxing electrodes 3 .

[0034] The specific working process of the melting zone 1 of the present invention is as follows: when the raw material is pushed into the first chamber 108 of the melting zone 1 through the feeding port 106 under the action of the feeder, the raw material in the first chamber 108 begins to melt under the heating action of the burner 2 and the flux electrode 3, and flows to the second chamber 109 with the glass liquid; with continuous heating, the raw material becomes molten glass liquid, and by adjusting the gas volume of the burner 2 and the current value of the flux electrode 3, the temperature measured by the upper thermocouple 4 and the lower thermocouple 5 of the first chamber 108 reaches the set temperature and remains stable, and the glass liquid contains a large number of bubbles at this time; when the glass liquid passes through the rear part of the first chamber 108, the temperature of the lower thermocouple 5 of the first chamber 108 is increased. The temperature reaches a temperature at which the clarifier in the raw material reacts violently and releases a large amount of oxygen, which begins to combine with the bubbles in the glass liquid, and the clarified gas collides violently with the gas in the bubbles and aggregates in large quantities, and the small bubbles quickly turn into large bubbles. When the glass liquid enters the rear part of the first chamber 108, the temperature of the lower thermocouple 5 continues to rise, the clarifier continues to react, and the clarified gas continues to be released, thereby making the bubbles in the glass liquid larger and larger. When the glass liquid flows through the second chamber 109, the temperature of the glass liquid reaches the highest, at which time the viscosity of the glass liquid is the lowest and the thickness of the glass liquid is the thinnest, and the bubbles in the glass liquid are quickly discharged, and the clarified glass liquid flows to the clarification homogenization device 6 through the discharge port 107.

[0035] The clarifying and homogenizing device 6 is made of zirconium and / or platinum, platinum-alloy material. In order to facilitate the discharge of bubbles, the temperature of the glass liquid in the clarifying and homogenizing device 6 is 1580°C and the pressure is -0.5Mpa. The clarifying and homogenizing device 6 is provided with a vacuum hole, and the vacuum hole is connected to a vacuum pump through a vacuum pipeline. A pressure sensor is provided on the vacuum pipeline to ensure that the clarifying and homogenizing device 6 is negative pressure. The height of the glass liquid level 7 in the clarifying and homogenizing device 6 is 0.21m.

[0036] The glass plate preparation method of the present invention is as follows: after the glass raw materials are evenly mixed, they are fed into the melting zone 1 from the feeding port 106, and the burner 2 and the flux electrode 3 are adjusted by the above method to obtain a homogenized and clarified glass liquid, which is then led out from the discharge port 107 to enter the clarifying and homogenizing device 6 for secondary bubble removal. According to the different glass components, the negative pressure value in the clarifying and homogenizing device 6 is adjusted to obtain high-quality glass liquid, which then enters the molding process and the annealing process for eliminating residual stress in the molded glass product, and is cut, ground, polished, and finally cleaned and packaged to obtain a glass plate.

[0037] Examples 1-9

[0038] The formula of the low-density and high-transmittance display glass plate of Examples 1-9 is shown in Table 1:

[0039] Table 1: Formula of low-density high-transmittance display glass plate of Examples 1-9

[0040]

[0041] The formulas of the display glass plates of Comparative Examples 1-6 are shown in Table 2:

[0042] Table 2: Formulation of display glass plate of Comparative Examples 1-6

[0043] Composition (wt%) Comparative Example 1 Comparative Example 2 Comparative Example 3 Comparative Example 4 Comparative Example 5 Comparative Example 6 <![CDATA[SiO2]]> 61.1523 60.9023 60.8017 60.896 61.15 61.15 <![CDATA[Al2O3]]> 21.19 21.19 21.19 21.19 21.19 21.19 <![CDATA[B2O3]]> 2.35 2.35 2.35 2.35 2.35 2.35 MgO 4.91 4.91 4.91 4.91 4.91 4.91 CaO 4.32 4.32 4.32 4.32 4.32 4.32 SrO 5.61 5.61 5.61 5.61 5.61 5.61 BaO 0.21 0.21 0.21 0.21 0.21 0.21 <![CDATA[ZrO2]]> 0.01 0.01 0.01 0.01 0.01 0.01 <![CDATA[P2O5]]> 0 0.25 0.0023 0.0023 0.0023 0.0023 <![CDATA[Fe2O3]]> 0.016 0.016 0.016 0.27 0.016 0.016 <![CDATA[MoO3]]> 0.0017 0.0017 0.35 0.0017 0.0017 0.0017 <![CDATA[SnO2]]> 0.15 0.15 0.15 0.15 0 0.23 SnO 0.08 0.08 0.08 0.08 0.23 0

[0044] Comparative Example 7

[0045] The difference from Example 1 is that the surface current density of the flux electrode 3 is 1.9 A / cm 2 The surface current density of the fourth and fifth columns of fluxing electrodes 3 accounts for 18% of the surface current density of all fluxing electrodes 3 .

[0046] The performance tests were conducted on the display glass plates prepared in Examples 1-9 and Comparative Examples 1-7. The test results are shown in Table 3-4:

[0047] Table 3 Performance test results of display glass plates prepared in Examples 1-9

[0048]

[0049] Table 4 Performance test results of display glass plates prepared in Comparative Examples 1-7

[0050]

[0051] As shown in Table 1-2, compared with Comparative Examples 1-7, the glass plate melted by the preparation method of the present invention has a lower density, a transmittance of more than 70% at 308nm, and significantly reduced amounts of unmelted matter and bubbles. The glass plate prepared by the present invention can be used not only as a glass substrate for display, but also as a carrier in the preparation process of high-performance display devices, especially in the manufacture of large-size panels, which can effectively solve the problem of low yield due to defects such as deformation (BOW shape) caused by excessive panel area.

Claims

1. A method for preparing a low-density and high-transmittance display glass plate, characterized in that: Based on oxides, the low-density and high-transmittance display glass plate includes the following components in weight percentage: SiO2 57.1-65.3%, Al2O3 14.2-22.7%, B2O3 0.01-4.3%, ZrO2 0.01-1%, P2O5 0.0001-0.05%, MoO3 0.0002-0.01%, Fe2O3 0.005-0.3%, SnO2 0.1-0.2%, SnO 0.01-0.1% and RO 13-21%; wherein RO is at least one of MgO, CaO, SrO and BaO; The method for preparing the low-density and high-transmittance display glass plate is as follows: the components are mixed evenly, and then the components are put into a kiln for melting to obtain a glass liquid, which is then clarified twice in a clarification process, and then formed in a molding process, and the formed glass plate is annealed and cooled before being cut, and finally ground, polished, cleaned, dried, and packaged; The kiln comprises a melting zone (1) and a clarification and homogenization device (6) which are connected to each other. The melting zone (1) is a closed area consisting of a front wall (101), side walls (102), a rear wall (103), a furnace bottom (104) and an arched top. A hanging wall (105) is arranged on the arched top of the melting zone (1) to divide the melting zone (1) into a first chamber (108) and a second chamber (109). The front wall (101) of the melting zone (1) is provided with a feeding port (106), the rear wall (103) is provided with a discharging port (107), and the side wall (103) is provided with a discharge port (108). A plurality of pairs of burners (2) are respectively arranged at the first chamber (108) and the second chamber (109) on the furnace (102), and the plurality of pairs of burners (2) are arranged at intervals along the length direction of the furnace; a plurality of fluxing electrodes (3) are respectively arranged at the furnace bottom (104) of the first chamber (108) and the second chamber (109); a plurality of upper thermocouples (4) are arranged at intervals along the length direction of the furnace on the arched top of the first chamber (108) and the second chamber (109), and lower thermocouples (5) are arranged at intervals along the length direction of the furnace on the furnace bottom (104); The burners (2) are provided in 5 to 8 pairs. When the height of the melting zone (1) is set to G, the height of the burners (2) from the glass liquid surface (7) is greater than 0.3G. The burners (2) use natural gas-oxygen and natural gas-air for combustion. According to the flow meter, the ratio of the natural gas-oxygen burner (2) to the natural gas-air burner (2) is 3:

1. When the burners (2) use natural gas-oxygen, the ratio of natural gas to oxygen is 1:1.9, and when the burners (2) use natural gas-air, the ratio is 1:0.

3. When the length of the melting zone (1) is set to Cz, a fluxing electrode (3) is arranged on the center line of the furnace bottom (104) in the length direction of the first chamber (108) at a position 0.03Cz-0.08Cz away from the feeding port (106); behind the fluxing electrode (3), a plurality of rows of fluxing electrodes (3) are arranged at intervals along the width direction of the melting zone (1), and the distance between the fluxing electrodes (3) close to the two side walls (102) and the side walls (102) is greater than 600mm; on the furnace bottom (104) of the second chamber (109), two rows of fluxing electrodes (3) are symmetrically arranged at a position 0.05Cz away from the discharge port (107); the height of the fluxing electrode (3) in the first chamber (108) is greater than 100mm, and the height of the fluxing electrode (3) in the second chamber (109) is 400-800mm higher than the fluxing electrode (3) in the first chamber (108); The surface current density of the flux electrode (3) is 0.5-1.6 A / cm 2 The total surface current density of the fluxing electrodes (3) in the first chamber (108) accounts for 70-90% of the total surface current density of all fluxing electrodes (3).

2. The method for preparing a low-density and high-transmittance display glass plate according to claim 1, characterized in that: The melting zone (1) is rectangular, and its length-to-width ratio is 3-3.5:1; when the height of the melting zone (1) is set to G, the distance between the bottom edge of the feeding port (106) and the glass liquid surface (7) is greater than 0.2G.

3. The method for preparing a low-density and high-transmittance display glass plate according to claim 1, characterized in that: The fluxing electrodes (3) are one or both of molybdenum-zirconium electrodes and tin electrodes. When the two fluxing electrodes (3) are used simultaneously, the number of molybdenum-zirconium electrodes is greater than the number of tin electrodes.

4. The method for preparing a low-density and high-transmittance display glass plate according to claim 1, wherein: Of the heat provided by the fluxing electrode (3) and the burner (2), the heat provided by the fluxing electrode (3) accounts for more than 70%.

5. The method for preparing a low-density and high-transmittance display glass plate according to claim 1, wherein: The temperature of the glass liquid in the clarification and homogenization device (6) is ≥1500°C and the pressure is 0 to -1.5 MPa; the height of the glass liquid level (7) in the clarification and homogenization device (6) is 1 / 2 to 2 / 3 of the height of the pipeline at the device level.

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