My friends and I made adult clothing protectors, we had a hard time finding old shirts at the thrift stores for a reasonable price. Plus there weren't many dress shirts available. Then we had to cut them up so the front was rounded around the neck. We found them to be on the thin side and figured anything greasy or wet like coffee would go through to their clothes. So we ended up lining them with muslin. Now we just use two layers of flannel, so much easier and nicer.