What is plastic? It is defined as “a synonym with synthetic resin. A solid substance artificially shaped into a useful form, with highly polymers being the primary raw material.” In other words plastic is made out of highly polymers, its form can be artificially shaped as necessary, and it is in the solid state in normal conditions. But fabrics, rubber, paint, and adherents are excluded from plastic. A plastic stabilizer (additive) is referred to as a chemical substance that makes the processing of plastic or synthetic resins easier and is added in processing or polymerization process to complement or improve weak physical properties of such products. Since the temperatures for processing and thermal decomposition of PVC resins are close to each other, coloring (oxidation by the atmosphere) is prone to happening when products are processed, as hydrochloric acid escapes the products. When this happens, it damages the exterior of the products or the processing facilities. Sometimes discoloration or coloring can happen while the products are in use due to ultraviolet rays, or depreciation of the durability of the products can be brought about. That is why PVC stabilizers are used to enhance the quality of products, prevent PVC resins from any damage and prevent deterioration of the products.