Homebrew PCBs

I know this isn't PCBs but does anyone have any experience with the 
adhesive film that you expose to a positive or negative artwork & then 
use a chemicals to fix & to remove the colour section to make up text or 
artwork.

I used to use it years ago & was wondering if it is still available or 
where to get small qty economically.

We often used a silver & black version but it was available in a wide 
raange of colours.  It was used for instruction panels on equipment 
etc.  It seemed to stick well & last for ever when applied.

I can't even remember the name of it to look it up.

Regards,
Brian.