Aromatic TPU resins are mostly milky white, while aliphatic ones are colorless and transparent. When exposed to the natural environment, their yellowing resistance is also different, which is due to differences in the light stability of the structure.
There is an oxidizable methylene bridge between the two benzene rings of aromatic TPU. Due to thermal oxidation and ultraviolet light irradiation, it is easy to turn yellow during processing and use, so it is usually necessary to add a light stabilizer to make it less prone to yellowing. Discoloration, if the production process is not good, this TPU invisible car cover may turn yellow in less than 1 year.
Aliphatic TPU does not contain benzene rings, which changes the original structure that is easily affected by ultraviolet rays, so that it can achieve a long-term non-yellowing effect without adding a large amount of light stabilizers and maintain good transparency, whether for product processing or subsequent use. Helpfully, the material is also known as non-yellowing TPU.
Aliphatic TPU is used in invisible car clothing. Invisible car clothing is also called paint protection film. In the early days, PVC was mostly used as the material, but it was not scratch-resistant, and it aged quickly when exposed to the natural environment. It was easy to yellow and unsightly. Consumers don't buy it;
Therefore, thermoplastic polyurethane elastomer-TPU with self-healing function has gradually replaced PVC, which is more tough and can automatically repair scratches. However, the yellowing problem has not been well solved, which seriously restricts the product. The aesthetics are very disliked by consumers who pursue perfection;
In order to cater to the high-end market, it is natural to have better materials to upgrade invisible car clothing, so aliphatic TPU is also used in this automotive product, and is committed to creating a brand of domestic high-performance invisible car clothing.