SKALPELThat's one of the New Rules of the American Road: * Overtaking in high-risk, low-benefit situations is mentally and emotionally...
patrick
OK, if you want a detailed chemical explanation, here goes. Soft vinyl plastics (as opposed to things like PVC pipe) contain a large amount of plasticizers. The one that is almost universally used is dioctyl phthalate. It is a relatively high molecular weight, water insoluble, nontoxic compound. Over the course of time, the plasticizer will vaporize and leach out of the vinyl causing it to become stiff and brittle, which is when it cracks.
ArmorAll is an emulsion of dibutyl phthalate in water. Dibutyl phthalate has a lower molecular weight than the dioctyl phthalate in the factory soft vinyl. While it will plump up and soften the plastic (good) the lower molecular weight means that it is more volatile and more water soluble. Therefore it will be lost more quickly to the environment via vaporization and leaching. A nasty side effect is that it will take the original plasticizer with it as it is lost.
Armor All bad urban myth or trueI've never seen this happen. Typically, I just apply Armor All once in the winter, and 2-3 times in the summer. The dashboard doesn't seem to crack if I stop using it...
What this means to the end user is that if you start using ArmorAll you had better continue to do so, or your vinyl will degrade much faster than if you had done nothing.
Ordinary glbutt blocks UV anyway. Ever try to get a suntan through your windshield? Doesn't work. That is not to say that maximum tint is a bad idea. UV damage is not the only light-related way to destroy plastics. Your plan is a good one. -- Andy Williams - real address andywlms at ct2 dot nai dot net
