Doesn't it... 15:00 Mar 4, 2011
...just mean 'low or zero percentage' tint in the 4-colour print process?
As I understand it, the 'aplat' (actually printed in white ink) would be used if the pack were transparent or on a coloured ground, whereas if it was being printed on a white substrate, it would simply be the absence (near or total) of any printing, i.e. passively leaving it white instead of actively printing it white.
That's how I understand what they're describing, though I don't know what the correct term is in graphics / printing jargon. | 
The translation workplace 
