平板显示用玻璃基板生产中玻璃液流经铂(合)金通道时气泡产生的原因分析与对策

Analysis on Blister Problem of FPD Glass Melt Resulting from Contact with Platinum Material and Its Solution

由于铂及其合金耐高温且化学性质稳定,不与玻璃熔体发生化学反应,因此广泛使用于玻璃基板等精细电子光学玻璃生产中的玻璃液熔化、澄清、调节(降温和均化)、输送和成型过程中。但当铂及其合金与玻璃液接触时,在两者界面会产生大量气泡。本文运用化学热力学和化学平衡理论论述了表面气泡产生的原因和影响因素,得出气泡的产生是由于玻璃液/铂(合)金界面处氧化反应生成的氢气逸出导致富氧层形成造成的,且推导出可用于抑制界面气泡生成的铂(合)金管道(容器)系统周围环境中氢气分压的计算公式,并据此提出了通过控制环境湿度和气氛中氧含量来抑制气泡生成的对策方案。

Patinum or platinum-based alloys are widely used in the melting, refining, conditioning （cooling and homogenizing） , flowing and forming processes in fine electronic optical glass production, such as FPD glass substrate, due to their excellent chemical stability. However, when the glass melt contacts with platinum or platinum-based alloys, a large amount of blisters are produced at the inter- face between metal and glass melt resulting from the oxidation reactions associated with the breakdown of OH groups and water dissolved in the glass melt. In this paper the causes of blister forming and effecting factors are elaborated based upon the theories of chemical thermodynamics and chemical equi- librium. Thus it is concluded that the blisters at the interface between metal and glass melt is caused by oxygeon rich layer formation at the interface due to the hydrogen permeation from the glass melt through the platinum layer and then into the atmosphere. Furthermore, the calculating formula of the partial hy- drogen pressure around the platinum system which can be adjusted to restrain from the interface blister- ing is deduced. According to the formula , several solutions are suggested to elimilate the blisters onglass surface.