Most of this type are called liquid crystal polymer and have high mechanical strength, particularly, high rigidity even without filling materials because of their self reinforcing property (reinforcing effect similar to filling material derived from the liquid crystal molecular orientation). In addition, some of them have the highest heat resistance among all the thermoplastic resins. The material organization is anisotropic with a very small thermal expansion coefficient, similar to metals, in the flowing direction as well as a very small shrinking percentage, almost zero, however, in the direction perpendicular to the flowing direction, the mechanical strength is reduced with a larger thermal expansion coefficient and shrinking percentage. It has the highest heat resistance among thermal plastic resins with 240?C of continuous operating temperature and 300?C of short-term heat resistance temperature. Self lubricates and excels particularly in impact resistance, fatigue resistance, radiation resistance and chemical resistance (except strong sulfuric acid), as well as electric insulation and flame resistance. It exhibits fast crystalline formation speed and low weld strength in molded articles. Also, its wettability as a filling agent is inferior with little reinforcing effect. Since it shows large dimensional variation in its crystalline process and large shrinking percentage during the forming process, it is not suitable for precision components.