So my older zodiac was fine and clean. Even put 303 protectant on it. I decided to cover it and it turned red!? (From gray) ... It had happened before and usually goes back to original color after a couple of days... What is going on?
I have noticed in certain conditions, if the material on my tubes gets warm and some water gets splashed on it, it will discolour (usually goes lighter) until the water has dried off and then the original colour returns, ive never got to the botom of why it is, but, because its not permanant, never found the need to ? .. there must be some superficial absorption going on
When certain polymers such as PVC are exposed to UV radiation the polymer molecules on the surface are converted to a complex structure made up of polyenes and this can result in a brownish discoloration often called UV discoloration which should disappear when exposure ends
What you describe is the opposite unless the cover somehow removes a surface coating exposing the above UV degradation
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