If you used a spray sealant like this: Papilio Spray Sealant
Sure, additional protection, but has there been any longevity studies done on these coatings?
I would think having that information would be critical.
People have been varnishing paintings and drawings for centuries, and HPS, at least, was demonstrated on Aardenburg to significantly increase the longevity of prints.
That paper is a little thick for what I'd be wanting. This is where our visions perhaps diverge SB.
Same here. What I'd really want is to be able to mount paper onto a flat piece of aluminium, wood or another material and display it much like a dye-sub or UV-curable metal print or a stretched canvas, with a surface durable enough to withstand such treatment, and the work itself being durable enough to withstand being un-mounted and re-mounted on a new substrate should the bond fail. You can't do that with untreated paper.
I've made (4) 44" x 75" big prints on canvas while we've been discussing this over the last 2 days. I'm printing as far out to the edge as possible. Eventually I will have to deal with how to mat/mount/frame. I'm not crazy about canvas stretching. Laminating down to dibond or gluing to wood panel seems like the eventuality. Too bad our vacuum process isn't available right now. 
I'm not a huge fan of canvas for most photos, but use it because it's lightweight, cheap, easily shipped in the unstretched form and seems popular. The issues are with texture and flatness. The even, regular pattern of canvas isn't as aesthetically appealing as the more random, natural-looking texture of paper or the mirror-like gloss of metal, while canvas, no matter how well-stretched, never ends up truly flat like a metal or flat-mounted paper print - there's always a bit of a curve or bulge to it. Some images work well with it, but, even then, I generally prefer those shots on matte paper. Still, mounting canvas onto a flat material solves all the problems except the texture - it gives perfect flatness, is tough enough for unframed display and is strong enough to be dismounted and remounted should the adhesive fail.
