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.