Who was the bright spark that sought heat can escape through 2 layers of plastic?

I took the trouble to take my phone to pieces today. I think I have identified where the processor is located which is also the point that gets the hottest this is because there is a large piece of metal which is probably meant to be the heatsink. However it does beg the question as to why oh why is this heatsink covered in plastic when there is already a plastic cover across the back of the fair phone. I believe there have been complaints about process overheating and I’m pretty sure that I have had a number of crashes due to this so why oh why has always plastic been piled on top of the processor? I’m rather minded to take a dram ought to my phone and remove this section of plastic to expose the heatsink. It is extremely pointless having a heatsink when you insulated from the surrounding air although I am sure the designers of the fair phone to are really bright sparks and already know this, or maybe not. I don’t know how much power the processor uses and how hot it should get but a 4 core 2.26 GHz processor is no doubt going to get a little toasty?

I fear the black plastic below the heat sink you talk about is the heat spreader. Or is there a misunderstanding?

The heat spreader will be attached the processor. If you take the cover off your phone you will find that this is behind the inner casing of the phone which means that there are 2 layers of plastic between the outside world and the heat spreader. Just think about it why do you have double glazed windows? Now think about that process are trying to dissipate heat with a sheet of plastic across it then a mother airgap and another sheet of plastic.

I see what you write this way … have I forgot an extra plastic part?

SoC->heat spreader (black plastic) -> heat sink (metal) -> (more plastic here?) -> air gap -> plastic frame.

I agree, better would be:

SoC->heat spreader (black plastic) -> heat sink (metal) -> metal cover touching the heat sink

But isn’t the display frame pressing against the heatsink so it exactly works like this? Maybe you can provide a better picture of the plastic part. The pictures on ifixit look pretty clever to me.