The Reason and Grade of TPU Film Anti-Yellowing
TPU raw material is with the comprehensive performance of anti-wearing, low temperature resistance, waterproof and high moisture permeability, with high tensile and elongation, can be processed to be multiple plastic finished products by extruding, casting or blowing process.
Under the long period irradiation of ultraviolet rays, TPU film is easy to be aging and yellowing, which lead to the performance lost, and the lowing down of the product value.
Why TPU film will be yellowing ?
TPU film will be yellowing under the illumination of national sunshine, ultraviolet, or heat, oxygen, stress, trace water, impurity or improper process.
There are 3 factors for TPU film to be yellowing: 1. Long time illumination 2 Oxidation reaction 3 Irradiation of ultraviolet
There are 5 grade for anti-yellowing: Grade 5 is absolute anti-yellowing; Grade 4 is little yellowing; Below Grade 3 is conspicuous yellowing.
We POLYAN supply excellent quality TPU film, anti-yellowing above grade 4.