Opti-Seal durability

[Catdog]

Hi all.

 

I put a coating of Opti-Seal on my windscreen so if it rains while I'm driving the theory says water beads nicely and runs off, like RainX.

 

It works very well, the rain water on the glass beads furiously into tiny drops until I hit about 60km/h, then it starts to form larger drops which slide back leaving clear vision. The problem I encountered leading to this question is a layer of dust build-up on the screen lead to me using the wipers, they swept the screen maybe 7 or 8 times in total. The Opti-Seal had only been there about 2 weeks when this happened.

 

So, would this have affected the Opti-Seal coating? I thought it might, so I cleaned the screen with Isopropyl and reapplied. But having thought about it some more, I think reapplication probably wasn't required. My logic is we wash our cars many times in between applications of sealant (but not with the same physical pressure a wiper applies).

 

What are your thoughts?