Somebody Please Explain Protective Spray To Me

I started making Piezo prints in 2001 - first using Sundance inks, as I recall, then PiezoTone and now K7 . My prints still look great. Back then the entire focus was on the inks, with emphasis placed on 100% pigment composition for maximum longevity. Paper issues were not initially addressed. Then we learned that atmospheric conditions can detrimentally affect the paper, bringing about a different mode of failure. This is, I assume, why some people spray their prints. I have not experienced paper failure with the two mat papers I use, Photo Rag and Innova Smooth Cotton. Quite possibly, my thinking is stuck in 2001.

Can somebody please illuminate my understanding of the pro and con arguments associated with protective spray on mat papers? (I think we’re talking about an aerosol after-treatment, not the in-line Gloss Optimizer.) If the spray is a varnish, don’t we know from museum oil painting experience that varnish darkens or becomes opaque with time? What is considered the current best practice, and why?

Thank you.


This response to my direct query from David Williams, of Innova Art Ltd.: “If a print will be framed behind glass, there is no need for any varnish. Yes varnish will yellow. We recommend a varnish for our canvas products since they are usually displayed without glass and need some protection from the environment (pollution, handprints, cleaning solutions, etc.). Some people do apply protective sprays to paper since the matte surface can be easily damaged between the time a print is made and when it gets into a frame.”

A while back I searched for a coating for my Pt/Pd prints (to enhance dMax) but could never find one guaranteed not to crack or degrade.

I eventually settled on K7 Carbon pigment inkjet on matte rag paper for the best combination of longevity and image quality.

Displayed behind glass, I prefer matte prints: the dMax is the same as glossy prints and although they require careful handling to avoid scratches, there are fewer distracting reflections.

Apparently next year our friends here will be releasing an improved ink set for K7, based on a nano-tech Carbon pigment that promises greater dMax… I’m really looking forward to that !

I can confirm. Our internal tests on our new (and laboriously created) “UltraHD” matte black ink shows a class-leading dMax of 1.81 on Hahnemuhle Photo Rag. This is an R&D ink so final production values (once everything is stable) may vary by .02 or .03 +/-. Still, this ink is very very very dark and will be well suited for both coated and uncoated paper printing.