Targets "pseudo-yellowing" caused by stain adhesion:
Some yellowing is due to dust and stains falling on the car body and not being cleaned in time. In response to this yellowing cause, a neutral detergent without abrasives can be used to try to remove the vehicle by deep cleaning first. Do not polish unless necessary, as polishing may damage the original protective coating of the garment and cause new problems. Pseudo-yellowing is generally localized, but if dust and stains completely penetrate into the TPU substrate, there is a possibility that it cannot be removed.
For yellowing caused by substrate glue:
The yellowing caused by the improper selection of TPU substrate and glue is generally a large-scale yellowing, which is irreversible, and it is recommended that the store negotiate with the owner to tear off and repaste it as soon as possible.
It should be emphasized here that the yellowing of the TPU substrate, the yellowing of the coating, or the pseudo-yellowing caused by dust stains will at most lead to the consequences of tearing off the film and repasting, but the yellowing of the glue is more risky, and the chemical reaction between the glue and the car paint has the possibility of damaging the car paint.
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How to avoid yellowing of car clothing?
Yellowing is a natural physical phenomenon, and it is impossible for the clothing to be completely non-yellowing under the effect of time, so here we will only discuss how to control the yellowing index of the clothing within the industry standard level 2 (slight discoloration):
1. First of all, for PVC, TPH, aromatic TPU material clothing, yellowing is basically inevitable, generally in 6 months to 2 years will occur obvious yellowing. In order to avoid yellowing of the substrate, aliphatic TPU material should be preferred. It should be noted that the yellowing rate of aliphatic TPU materials of different brands is also different, and it is necessary for casting factories and coating factories to carefully select substrate particles according to past industry experience.
2. The selection of car coating glue has greater exclusivity, and the coating factory should choose the glue brand and brand that have been fully tested and certified by the market, and be cautious of using some glue brands that have not been strictly tested and demonstrated by the market.
3. Good car habits are also very important, it is recommended that the owner wash the car at least once every two weeks, and go to the store every six months to maintain the car clothing, so as to avoid the surface stains from penetrating into the substrate as much as possible, resulting in "false yellow" to "true yellow".
