Try some PUL (don't know the full name) It is a stretch knit that is covered with water proof coating on one side. The 'mama's' that make their own diapers and 'rubber' pants use this. You can google/bing cloth diapers and come up with a few sites that sell the diapers and PUL. I had a lady I took care of in my home a few years ago and I made pads for her to sit on in her wheelchair. When she had accidents it didn't leak through.