Wood-plastic composites are thought to fade over time, and this is also a feature of WPC can not deny. In order to keep the production original color and extend the fading period, Barefoot has been researched continuously on WPC color persistence subject. Based on laboratory data and market experience, we summarize as following.
（1） UV Absorbing Agent
WPC board would occur fade under the condition of ultraviolet light, this is dur to the high-energy ultraviolet light destroys the molecular chain on the surface of polymer and other organic functional groups. So add a certain amount of UV absorbing agent in WPC board, can reduce the plastic and resin matrix composite’s oxidation-degradation reaction so that help the fading. But it is noteworthy that the UV absorbing agent can not solve significantly WPC fading problem, it just extend the fade time instead.
（2） Stable Colorant
In the process of WPC board production, we usually add stable colorant to slow fading problem. From the view of types, inorganic colorant ( such as iron oxide ), is more stable than organic colorant. What interesting is, the inorganic colorant will form free radicals inside the material or surface, then the degradation of WPC will accelerate. For example, the iron oxide has free iron or other metal ion which is strong catalysts for plastic. So inorganic colorants are usually protect the WPC surface from fade but accelerate the inside WPC oxidation-degradation reaction. For avoiding this reaction, what we do is add some anti-oxygen agent at the same time to ensure the production quality.