Dear Donia,
What type of fabric is best for a book support pillow?
Q. Dear Donia,
A. Dear Havva,
What an excellent question. The type of fabric is important when making exhibit mounts but it is equally, if not more important, is to ensure that the dyes in the fabric are stable and won't run.
Ideally, you would use a simple 100 percent cotton muslin in a natural color. This isn't stark white but more ivory and works really well with historic books. 100% polyester works well too. Whatever fabric you select, wash it first in a scent-free detergent and dry without a fabric softener or dryer sheet. This will remove any fire retardants in the fabric but will also give you a good idea if the fabric is colorfast.
Black can be a stable dye but it does not always hold up well over time. Maroon might look pretty but almost any shade of red does not respond well to light or water resulting in faded or bleeding fabrics.