why does clear phone cases turn yellow

Many clear phones cases are made of pvc,silicone and TPU materials.

TPU (thermoplastic polyurethane) and PVC (polyvinyl chloride) materials can turn yellow due to several factors. One major cause is exposure to UV radiation, which can cause the polymer chains to break down and change color. This process is known as photodegradation. Another factor that can cause yellowing is exposure to heat or humidity, which can also cause the materials to degrade and discolor over time. In addition, exposure to certain chemicals, such as bleach or solvents, can also cause yellowing of TPU and PVC materials. Finally, clear TPU and PVC materials may be more prone to yellowing because they do not have any pigments to mask the discoloration.

PVC, TPU, and silicone materials can turn yellow over time due to a process called oxidation. This occurs when the material is exposed to heat, light, or certain chemicals, which can cause the material to break down and yellow. Additionally, exposure to UV light can also cause the materials to yellow due to the breakdown of the polymer chains. The degree and rate of yellowing can depend on the specific type of material, its quality, and the conditions in which it is stored or used.

Clear phone cases may turn yellow over time due to exposure to UV radiation, heat, and/or chemicals. UV radiation can cause the plastic to degrade and turn yellow, while heat can accelerate this process. Chemicals from everyday use, such as hand creams or makeup, can also contribute to discoloration. Additionally, clear phone cases made from cheaper materials may be more prone to yellowing.