废液晶显示器面板偏光片化学剥离特性

废液晶显示器(LCD)面板的资源化回收利用中，需考虑对偏光片的处理。在超声波和加热作用下，利用强碱对废液晶显示器面板上的偏光片进行剥离，分析了温度、碱液浓度和超声波频率对偏光片剥离效果的影响。依次通过浓硫酸和王水对剥离偏光片后的玻璃基板进行酸浸，分析各浸出阶段的铟溶出特性。结果表明，在超声波作用下，在一定温度（50~80 ℃）内，利用NaOH溶液可实现废液晶显示器面板偏光片的高效分离；当温度为70 ℃、超声波频率为45 kHz、NaOH浓度为0.1mol/L时，偏光片的剥离仅需37 min；NaOH溶液为0.1和0.3 mol/L时，化学剥离过程中未发生铟元素转移的问题。

Study on Chemical Stripping Characteristics of Polarizer from Waste LCD

The recycling process of waste LCD panel should take into consideration of the removal of the polarizer. With the aid of ultrasonic wave and heating, the polarizer was stripped by alkali solution. The influences of the temperature, concentration of alkali and ultrasonic frequency on the separation of the polarizer were analyzed. And then the glass substrate was extracted by concentrated sulfuric acid and aqua regia successively. The leaching characteristics of indium were also analyzed. The result showed that in the presence of ultrasonic wave and under the temperature range of 50-80 ℃, the polarizer could be separated efficiently from waste LCD panel by sodium hydroxide solution. Besides, the separation of the polarizer only took 37 min with the temperature of 70 ℃, ultrasonic frequency of 45 kHz and NaOH concentration of 0.1 mol/L. The transfer of the indium did not occur during the process of the chemical stripping when the concentration of NaOH was 0.1 and 0.3 mol/L.