PREPRESS Stretch-free polyester plates
Is there a way to keep polyester plates from stretching? Try turning the plate over and using 500-grit wet and dry automotive sandpaper to scratch the back side at a 45° angle to the lead edge, in both directions. Then wet the back side and load it on the cylinder.
The scratches create pockets of air and water that cause the plate to stick to the cylinder. Remember that because it sticks so well to the cylinder, the plate will have to be removed by hand.