I put this up as a collage a few weeks ago. Then I painted it red, I just can't help myself then yesterday I started to over paint and the first coat started coming off. I do not know why. I glued the pages on with something acrylic so it should be compatible. So now I am going to gesso the whole thing and start again. All good, sticking on more pictures gives me something to do. Hope it doesn't happen again.