DE-112025000037-T5 - Alkali-free boron aluminosilicate glass with heat resistance, stability and high crystallization margin, as well as a manufacturing process for it.

Abstract

The present invention relates to the technical field of electronic glass, in particular an alkali-free boron aluminosilicate glass with heat resistance, stability and high crystallization margin, and a manufacturing process for it. The alkali - free boron aluminosilicate glass with heat resistance, stability and high crystallization margin, whose raw materials, given in mol percent, comprise: 68.54% to 72.82% SiO₂ , 11.84% to 13.5% Al₂O₃ , ≤ 2.23% B₂O₃ , 4.72% to 6.6% MgO, 4.65% to 5.8% CaO, 0.8% to 1.5% SrO, 3.2% to 3.79% BaO and 0.1% SnO₂ , where SiO₂ + Al₂O₃ is 81.63% to 84.66% and (MgO + CaO + SrO + BaO) / Al₂O₃ is 1.15 to 1.30 . The alkali-free boron aluminosilicate glass obtained with this application exhibits a high elongation point and a large crystallization margin, while also taking into account high heat resistance, stability and devitrification resistance.

Inventors

• Jing Lan
• Lihua Xu
• Zhao ZENG

Assignees

• CAIHONG DISPLAY DEVICES CO., LTD.

Dates

Publication Date

20260513

Application Date

20250731

Priority Date

20240929

Claims (10)

1. Alkali - free boron aluminosilicate glass with heat resistance, stability and high crystallization margin, characterized in that its raw materials, specified in mol percent, comprise: 68.54% to 72.82% SiO₂ , 11.84% to 13.5% Al₂O₃ , ≤ 2.23% B₂O₃ , 4.72 % to 6.6% MgO, 4.65% to 5.8% CaO, 0.8% to 1.5% SrO, 3.2% to 3.79% BaO and 0.1% SnO₂ , wherein SiO₂ + Al₂O₃ amounts to 81.63% to 84.66% and (MgO + CaO + SrO + BaO) / Al₂O₃ amounts to 1.15 to 1.30.
2. Alkali-free boron aluminosilicate glass with heat resistance, stability and high crystallization margin according to Claim 1 , characterized in that its raw materials, specified in mol percent, comprise: 69.12% to 72.82% SiO₂ , 11.84% to 13.1 % Al₂O₃ , ≤ 2.23% B₂O₃ , 5.28% to 6.59% MgO , 4.65% to 5.78% CaO, 0.8% to 1.5% SrO, 3.2% to 3.79% BaO and 0.1% SnO₂ , wherein SiO₂ + Al₂O₃ amounts to 81.63% to 84.66% and (MgO + CaO + SrO + BaO) / Al₂O₃ amounts to 1.15 to 1.30.
3. Alkali-free boron aluminosilicate glass with heat resistance, stability and high crystallization margin according to Claim 1 , characterized in that its raw materials, specified in mol percent, comprise: 69.33% to 72.82% SiO₂ , 11.84% to 13.1 % Al₂O₃ , ≤ 2.23% B₂O₃ , 5.28% to 6.59% MgO , 4.65% to 5.52% CaO, 0.8% to 1.5% SrO, 3.2% to 3.79% BaO and 0.1% SnO₂ , wherein SiO₂ + Al₂O₃ amounts to 81.63% to 84.66% and (MgO + CaO + SrO + BaO) / Al₂O₃ amounts to 1.15 to 1.30.
4. Alkali-free boron aluminosilicate glass with heat resistance, stability and high crystallization margin according to Claim 1 , characterized in that its raw materials, specified in mol percent, comprise: 70.5% to 72.82% SiO₂ , 11.84% to 13.1% Al₂O₃ , ≤ 1.23% B₂O₃ , 5.28% to 6.29% MgO , 4.99% to 5.01% CaO, 0.8% to 1.1% SrO, 3.54 % to 3.79% BaO, and 0.1% SnO₂ , wherein SiO₂ + Al₂O₃ is 83% to 84.66% and (MgO + CaO + SrO + BaO ) / Al₂O₃ is 1.15 to 1.29.
5. Alkali-free boron aluminosilicate glass with heat resistance, stability and high crystallization margin according to Claim 1 , characterized in that its raw materials, specified in mole percent, comprise: 72.82% SiO2 , 11.84% Al2O3 , 5.28 % MgO, 5.32% CaO, 1.1% SrO, 3.54% BaO and 0.1% SnO2 , where SiO2 + Al2O3 is 84.66% and (MgO + CaO + SrO + BaO ) / Al2O3 is 1.29 .
6. Alkali-free boron aluminosilicate glass with heat resistance, stability and high crystallization margin according to Claim 1 , characterized in that the expansion point temperature of the alkali-free boron aluminosilicate glass with heat resistance, stability and high crystallization margin is 735 °C or more.
7. Alkali-free boron aluminosilicate glass with heat resistance, stability and high crystallization margin according to Claim 1 , characterized in that the liquidus viscosity of the alkali-free boron aluminosilicate glass with heat resistance, stability and high crystallization margin is 203426 P or more and the crystallization margin is 80 °C or more.
8. Manufacturing process for alkali-free boron aluminosilicate glass with heat resistance, stability and high crystallization margin according to one of the Claims 1 until 7 , characterized in that it comprises the following steps: mixing, melting and refining the raw materials to obtain a refined glass melt, subsequently shaping a refined glass melt by means of an overflow down-draw process to obtain an alkali-free boron aluminosilicate glass with heat resistance, stability and a high crystallization margin.
9. Manufacturing process for alkali-free boron aluminosilicate glass with heat resistance, stability and high crystallization margin according to Claim 8 , characterized in that the melting temperature is 1590 to 1630 °C.
10. Manufacturing process for alkali-free boron aluminosilicate glass with heat resistance, stability and high crystallization margin according to Claim 8 , characterized in that the forming temperature is 1270 to 1300 °C.

Description

Technical field The present invention relates to the technical field of electronic glass, in particular an alkali-free boron aluminosilicate glass with heat resistance, stability and high crystallization margin, and a manufacturing process for it. State of the art With the continuous development of display technology, consumer demand for display devices is gradually shifting towards larger dimensions, high resolution, and high-resolution screens. Compared to thin-film transistor displays made of amorphous silicon, thin-film transistors made of polycrystalline silicon can transfer electrons faster and more efficiently and exhibit higher electron mobility. Therefore, polycrystalline silicon can be used to manufacture smaller and faster transistors, ultimately leading to the production of brighter and faster displays. However, in the manufacturing process of polycrystalline silicon transistors, the substrate is heated to 450–600 °C, which is a higher processing temperature than the peak temperature of 350 °C used to manufacture transistors from amorphous silicon. At such temperatures, the substrate glass is highly susceptible to deformation. In response to this, the heat resistance and stability of the substrate glass can be improved by adjusting the composition of the substrate glass, the forming process, and other techniques. This is mainly because glass with high heat resistance and stability (with a high elongation point) can prevent deformations due to poor heat resistance of the glass during the heat treatment process of the panel manufacturing process. Simultaneously, the entire production process of substrate glass made from polycrystalline silicon must be carried out at higher temperatures. The process temperature for substrate glass production is high. During the melting process, substances in the melting furnace can more easily attack the refractory materials in the production line, leading to a greater number of stone inclusions in the glass. Furthermore, a high forming temperature exacerbates the creep of overflow stones, significantly impacting the lifespan of the production line and increasing production costs. At the same time, the liquidus temperature of the substrate glass is directly related to the forming process and the product quality of the substrate glass. Only by controlling the liquidus temperature of the substrate glass below a specific temperature and increasing the difference between the forming temperature and the liquidus temperature (the crystallization margin) can the normal flow of forming production be ensured. The liquidus temperature of the substrate glass depends on factors such as the glass composition, the glass structure, and the glass phase separation. By testing the production process and the liquidus temperature of various formulations, the formulations can be selected or optimized. Therefore, the accurate measurement of the melting temperature, forming temperature and liquidus temperature of various substrate glass formulations is of practical importance for the formulation of the liquid crystal substrate glass production process, the stability of the forming process and the control of product quality. The currently disclosed substrate glass exhibits a relatively high crystallization margin and liquidus viscosity, which significantly reduces the risk of devitrification at cold spots in the molding system. However, the heat resistance, stability, and devitrification resistance of the substrate glass are still insufficient, and it is not possible to simultaneously guarantee high heat resistance, stability, and devitrification resistance. Content of the invention The object of the present invention is to provide an alkali-free boron aluminosilicate glass with heat resistance, stability and a high crystallization margin, in order to solve the prior art problem that alkali-free boron aluminosilicate glass cannot simultaneously exhibit high heat resistance, stability and devitrification resistance. The present invention further provides a manufacturing process for an alkali-free boron aluminosilicate glass with heat resistance, stability and high crystallization margin, in order to solve the problem of the state of the art. The technical challenge is that alkali-free boron aluminosilicate glass cannot simultaneously exhibit high heat resistance, stability, and devitrification resistance. Specific embodiments In the current state of the art, alkali-free boron aluminosilicate glass cannot simultaneously offer high heat resistance, stability, and devitrification resistance. The present invention provides an alkali-free boron aluminosilicate glass with heat resistance, stability and a high crystallization margin, the raw materials of which, given in mol percent, comprise: 68.54% to 72.82% SiO₂ , 11.84% to 13.5% Al₂O₃ , ≤ 2.23 % B₂O₃ , 4.72% to 6.6% MgO, 4.65% to 5.8% CaO, 0.8% to 1.5% SrO, 3.2% to 3.79% BaO and 0.1% SnO₂ , wherein SiO₂ + Al₂O₃ amounts to 81.63% to 84.66 % and