gimmee 3 paragraphs of affort to explain EXACTLY what you are doing, where you need help, and whastever other limitations or considerations may apply, to increase the chances that I, or others are not wasting their time replying to an entirely too vague inquiry.
...for now, I can say that if "trans" means translucent... & if "clear black print so the backlight can pass" means black ink, printed on clear vinyl & applied to white plex, so it looks black in the day, and white at night... then you want to use the perforated material commonly used for windows on vehicle wraps...
..but if your vague & cryptic post doesn't mean what I guessed... then I am a perfect example of someone who just wasted 5 minutes of a Saturday morning that I will never get back... because of a lazy post that doesn't speel out exactly what is going on.