Backpacks are painted with Acrylic paints. These types of paint eliminate the need for turpentine and gesso, and can be applied directly onto canvas. More than anything, this kind of paint can be waterproof, permanent, light-fast. You can wash the shoes, but please DO NOT brush the paint heavily or use any bleach, washing machine is not allowed. As an added step the backpacks are sprayed with Camp Dry making these hand painted Nylon backpacks waterproof.