Plastic or resin
Generally, the non-metallic materials used to make spectacle frames mainly use synthetic resin as raw materials, which are divided into two categories: thermoplastic and thermosetting resin.
It is a material used to make glasses for a long time. It has been rare in the early 21st century. Celluloid has good plasticity, high hardness, and can be dyed into various colors. The disadvantage is that it is poor in stability and easy to corrode and age; it will emit camphor odor when rubbed. Can be used to identify this material. Due to the characteristics of easy aging and burning phenomenon, it has been rarely used.
2. Acetate fiber
Compared with celluloid, acetate is not flammable. Generally, chemical racks are mostly made of this material. According to the processing method, they can be divided into injection racks and plate racks.
3. Injection frame
Low cost, with seams and roughness, used for low-end sunglasses (heat-processed manufacturing).