Hahnemuhle Protective Spray will become your favorite print protector. This product also works on canvas projects since a varnish does a better job in terms of long term protection. And, since canvas may find itself in an abrasive environment, this product is a good choice.
Ozone-friendly low-odor aerosol spray that significantly improves wet-fastness
In addition to protecting delicate inkjet images from moisture, it also shields images from fingerprints and harmful UV rays