The exposed area is sometimes white sometimes a duller version of what one
Ours were hit and miss.
We used our school emblem fleur de leys cut from construction paper and
shells and fake and real flowers and leaves.
It doesn't make the fabric stiff.
It can be bought at almost any art supply.
There is a new book out that explains it all too.
Just do a "google" search for Sun Painting.
It would make a great summer camp project.
If I can afford it, I'd love to have them cut their names out of const. paper
and do a bath towel with all sorts of plastic summer objects. (100% cotton