[SteveB]

Huw

Over many years working in the display industry, the painting or screen printing of 'perspex' acrylic, pvc and polycarbonate could always present problems; by attacking the surface to cause wrinkling of the 'paint',clouding of the material, poor adhesion or stress cracking.

I would recomend that you get some off cuts of the exact material the window is made from and do some tests. You could try spraying screenprint ink from an airbrush, Sericol inks or a local screenprint firm could help with a choice of ink type and surface preparation.

Regards

Steve