I’ve tried other materials. PETG is a clear plastic in 0.50 mm thickness that is available at Ponoko.
What can I say. The cards are invisible! PETG isn’t a good material for business cards. The thickness 0.5 mm is better than the 3.0 mm of acrylic but … again invisible. Put the card down and you’ll never see it again. Voila! Magic!
The plastic also fractures. I’m sure there is a technical term for it, but I don’t know it. If you look at the Right Side, Top card and the Left side, Middle card, you can see the corners are cut. They arrived from Ponoko like this. The plastic itself is very flexible, but the fractures also make this a bad material to use for business cards.