I have been using this same sheet of bubble for a couple of months. It has printed many colors and is starting to get a bit stiff, but I will not discard it until it is useless. I put two colors of yellow acrylic onto my palette and used a foam brush to apply it to the bubble side of the bubble wrap.
Below, is the postcard I will be printing first.
I lay the painted bubble wrap paint side down onto my work surface and press firmly, making sure all the bubbles make contact with the paper underneath.
Here is one postcard printed with bubble wrap. This one has three layers at this point. Gesso, printed masking tape, and bubble wrap printing.