She is doing one from heavy fabric (lawn furniture pillow type) with a tropical foliage print in the center and borders of a complimentary green. It will be reversible with a slightly different foliage print on the other side. She is not planning on using any batting or interfacing.
The article she saw had mentioned a particular method of 'sealing' or 'coating' the fabric after it was done. This is what she's wanting to know what to use.