Stiff fabric
 

I recently bought some fabric at the thrift store---it is cotton, looks like it may be older but so stiff. What do they do to fabric to make it stiff and will it wash out? Other than the stiffness it is nice fabric that I would like to use. It was enclosed in plastic bags so did not realize it was so stiff.

Wash it to see how it holds up and behaves. Really stiff fabric imho inferior fabric.

could be heavily starch...which I do since easier to wk with and match seams...will wash out if it is starched.

Could be excess dye or sizing, if so, washing should soften it. It may also be a home dec fabric, like polished cotton which is a bit heavier and stiffer than quilting cotton. And, finally, are you sure it's 100% cotton? Some blends are very stiff.

I would wash it with detergent. If it is still stiff afterwards, I would use it only in utility quilts. If the stiffness is gone, I would starch it to restore stability before cutting and piecing.

Manufacturers add lots of chemicals and sizing to fabric before it is put on the bolt; washing will get rid of them. Some people automatically wash new fabric because they are allergic to some of the chemicals in new fabric.

You can wash it, roll it up while still wet, put in a plastic bag and put in the freezer for 24 hours. The Irish used to put their new linen items out in the snow to soften them