Liquid crystals find wide use in liquid crystal displays, which rely on the light modulating properties of certain liquid crystalline substances.
The optical properties of the liquid crystal layer are modified by applying an electric field to it. Liquid crystals do not emit light directly and are therefore dependent on a light source (in general cold cathode fluorescent lamps or LEDs). TheCCFLs are hazardous and must therefore be treated cautiously.
Liquid crystal layers contain indium, which is a valuable rare metal.
Large liquid crystal layers are mainly used in computer and TV monitors. Smaller liquid crystal layers are also found in displays of printers, fixed line telephones, photo cameras, etc. The liquid crystal layer is located between two (dark) polarizers, which is enclosed by several other, usually white or transparent plastic layers.
Caution during storage
Store the LCD layers in a recipient. If possible, avoid breakage of the layers.
In the ITO (indium tin oxide) electrodes of the liquid crystal module, small amounts of indium (In) can be found. Indium is a rare metal which is increasingly in short supply. Due to the small volume of the liquid crystal layer and the potentially rising price of indium, it is recommended to store them for future indium recovery.
Another option is the disposal of the liquid crystal module (without CCFL) in a landfill or its controlled incineration.
Source of information
Dismantling Guide for IT Equipment, which was elaborated within the SRI project and financially supported by SECO and UNIDO, June 2015