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Why does car PPF yellowing (1)?

DATA: 2022-12-15

Car PPF yellow, refers to the transparent Película PPF exposed to natural light, ultraviolet, heat, oxygen, chemical erosion, water and so on the environment, as well as improper production process caused by the car color yellow phenomenon.


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In theory, all items under the influence of time and external factors, will occur a certain degree of yellowing, this is the law of nature. Car owners can make specific analysis and judgment according to the following factors that may lead to yellowing of transparent PPF-- the three main factors that determine whether the PPF film will yellow: substrate, glue, coating. Among them, the substrate is the most likely to cause yellowing.


Maximum possibility of clear PPF yellowing: substrate


PVC is the only material that will turn yellow in a very short time. You can think of it as hard plastic. It has poor stability to light and heat, and it is easy to yellow.

However, the lacquer protective film has developed to the present, and the material has been optimized for several generations. Now the car protective film simply named after PVC has disappeared. Therefore, the base material of car and clothing that is most likely to cause yeloration is basically TPH material.


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TPH material is actually to add plasticizer to PVC material, so that the original hard plastic into a relatively good construction of soft plastic, but its nature is still PVC, so TPH material is very easy to yellow.


In addition, aromatic TPU base material, aromatic TPU base material contains benzene ring, easy to be affected by ultraviolet oxidation, irreversible yellowing, so it is completely unsuitable for automotive TPU base material.


Therefore, aliphatic TPU must be selected as the correct substrate for PPF, because its structure does not contain benzene ring, and the molecular arrangement density is dozens of times that of aromatic, which is not easy to be affected by ultraviolet oxidation and very resistant to yellow. Aliphatic TPU is generally used in high-end footwear, LED accessories, optical lenses, invisible clothing and other areas that have requirements for yellow resistance.