I had two of our cars tinted at Sun-X in Autocentro Cubao back in 1999 for P2,700 each...
I thought 3M super black is not supposed to turn
PURPLE 
? or does it? because just after 4 years i noticed both of the cars tint started turning purple...just like what happened with my previous tint which was the cheap US Gila type...
the reason i paid for the more expensive 3M is because I didnt want it to turn purple!!!
any comments would be appreciated...
thanks
PS- the tint has the 3M logo inside made of small dots....