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Greg Miller
25-Jul-2006, 10:55
I have been printing exclisively on matte paper for a while so I have not had to worry about outgassing. But I was very impressed with test prints on Hahnemuhle Fine Art Pearl paper. So I am going to print a project on this paper. Does anyone have any experience with outgassing with this paper? Is the routine the same as other luster papers in terms of having prints spend some time under an absorbant paper in order to prevent outgassing from casung a problem after the framing?

Thanks.

chris jordan
25-Jul-2006, 11:11
Yep, treat it the same as the other RC papers. The outgassing comes from the ink, not the papers, so I would think the matte papers would have the same outgassing issue. Are people saying the matte papers don't need the outgassing treatment?

Greg Miller
25-Jul-2006, 11:21
Thanks - I have not had a problem with outgassing with matte paper. The Matte paper seems to abosrb everyting and not let go (that's my "scientific" explanation). I recently left a framed print on Hahnenuhle German Etching Paper sit in direct sun all day long and encountered no outgassing at all. It was pretty intense sun that would have created outgassing on a luster paper in under 5 minutes.

Michael Gordon
25-Jul-2006, 11:54
Outgassing is typically the province of poly-based papers (like Premium Luster) due to reduced breathability. I've never had any outgassing with Photorag (fiber base). I can't speak for Fine Art Pearl; I've still never even seen it.

chris jordan
25-Jul-2006, 12:25
The Fine Art Pearl is coated with a material that is similar to the coating on the RC papers. It is not an RC coating, but for outgassing purposes it looks like it will behave the same. It's a gorgeous paper, by the way, by far the best inkjet printing paper I have ever seen. Hahnemuhle has a pretty good 7800/9800 profile on their site, downloadable for free. Try printing with +10% ink density for an even richer look.

Greg Miller
25-Jul-2006, 12:30
I did a side by side comparison of a print, 1 printed on Hahnemuhle German Etching paper and the other on the FAP (both using the stock Hahnemuhle profile). The FAP print had much richer blacks and showed much better capability with small tonal gradations. I was very impressed and also very impressed with the lack of gloss differential using the K3 inks on the 9800.

Chris - Thanks for the tip on the +10% density. I'll give that a try.

Bruce Watson
25-Jul-2006, 12:31
Outgassing has been covered in great depth in the yahoo EpsonWideFormat (http://groups.yahoo.com/group/EpsonWideFormat/messages) group. Many times. Did I say "great depth?" Search the archives and see for yourself. Weeks and weeks worth of postings.

The outgassing problem comes from pigment ink base. It uses glycols for clogging performance and glycerins to help evaporate the glycols once printed to the substrate. When the work gets framed it vastly restricts air movement at the print surface (which is one of the points of framing, yes?). Then the gallery lights (room lights, sunlight, whatever) heat the print. The glycols evaporate off the print but have nowhere to go, so they condense out on the nearest cool surface in the enclosed space. And you end up with an oily mess on the inside of the glazing.

The only way to get them off the substrate after printing is heat and air movement. It's a fantasy, unsupported by science, that close proximity to "absorbent paper" is going to make low volitility molecules evaporate from a substrate. I know Epson said it, but that doesn't make it right.

Interestingly, this is a problem with pigment inks in general. I have this same problem with PiezoTone inks. And yes, it does happen with HPR and other matte papers.

The cure is a hand held hair dryer. Low heat, high fan. Works like a charm. Lacking that, keep the print warm and let it get plenty of air. Hanging in a warm studio for a few days might be sufficient. I've heard that six weeks in a cold studio in winter wasn't enough.

Side effects of driving off the glycols and glycerins include increased Dmax (as much as a full stop with PiezoTones) and gamut (slight but visible with UltraChromes). This is one of the reasons that the print from yesterday looks better than you remember it ;-) Think of the changes you get from drying an inkjet print as the equivalent of highlight drydown of darkroom prints.

chris jordan
25-Jul-2006, 12:41
I know people say that putting paper in close proximity doesn't do it, but my experience is that it does. My method is to lay a sheet of newsprint on top of the print and roll it flat with a tube, to create the tightest seal possible. Then I lay a sheet of foamcore on top of that. Within about 24 hours, the newsprint is noticably soft, wrinkled and damp feeling in the place where it covered the inks. Where it didn't cover the inks, it is just the same as when I laid it down. I then replace the paper, do it again, and the second time there is far less of the damp wrinkly effect. A third time produces none, even after many days. So I think Epson's system actually does work.

I haven't tried the blow-dryer method. How long do you apply the heat for, and how do you know when you've done enough?

Greg Miller
25-Jul-2006, 12:42
Outgassing has been covered in great depth in the yahoo EpsonWideFormat (http://groups.yahoo.com/group/EpsonWideFormat/messages) group. Many times. Did I say "great depth?" Search the archives and see for yourself. Weeks and weeks worth of postings.

The outgassing problem comes from pigment ink base. It uses glycols for clogging performance and glycerins to help evaporate the glycols once printed to the substrate. When the work gets framed it vastly restricts air movement at the print surface (which is one of the points of framing, yes?). Then the gallery lights (room lights, sunlight, whatever) heat the print. The glycols evaporate off the print but have nowhere to go, so they condense out on the nearest cool surface in the enclosed space. And you end up with an oily mess on the inside of the glazing.

The only way to get them off the substrate after printing is heat and air movement. It's a fantasy, unsupported by science, that close proximity to "absorbent paper" is going to make low volitility molecules evaporate from a substrate. I know Epson said it, but that doesn't make it right.

Interestingly, this is a problem with pigment inks in general. I have this same problem with PiezoTone inks. And yes, it does happen with HPR and other matte papers.

The cure is a hand held hair dryer. Low heat, high fan. Works like a charm. Lacking that, keep the print warm and let it get plenty of air. Hanging in a warm studio for a few days might be sufficient. I've heard that six weeks in a cold studio in winter wasn't enough.

Side effects of driving off the glycols and glycerins include increased Dmax (as much as a full stop with PiezoTones) and gamut (slight but visible with UltraChromes). This is one of the reasons that the print from yesterday looks better than you remember it ;-) Think of the changes you get from drying an inkjet print as the equivalent of highlight drydown of darkroom prints.


This request is specific to the Hahnemuhle Fine Art Pearl. I have not seen that specifically mentioned.

Bruce Watson
25-Jul-2006, 12:49
This request is specific to the Hahnemuhle Fine Art Pearl. I have not seen that specifically mentioned.
Outgassing is specific to pigment inks, not any particular substrate. HFAP will outgas similarly to all the other substrates.

Greg Miller
25-Jul-2006, 12:56
Outgassing is specific to pigment inks, not any particular substrate. HFAP will outgas similarly to all the other substrates.

My experience is there is no outgassing with pigment inks on matte papers. FAP seems (to me anyway) a different paper than previous papers (matte ior RC) and therefore warranted a request for expereinces specific to this paper. I apologize if my reasoning was faulty.

Bruce Watson
25-Jul-2006, 13:07
I know people say that putting paper in close proximity doesn't do it, but my experience is that it does.
If you are happy, continue on. But you might have fun discussing this with a chemist sometime ;-)


I haven't tried the blow-dryer method. How long do you apply the heat for, and how do you know when you've done enough?
Just a few seconds once the dryer is warmed up. Put your other hand under the paper - you'll feel it get damp first (the energy from the dryer going to drive out and phase change the fluids to vapors), then it will get dry (as the process ends), then it will start to heat up, then you move on. If you've done it with a paper like HPR, then RC papers take about the same treatment but you can't feel it nearly as well because of the resin barrier.

Some alternatives for big prints - hang them and light them for a while depending on how bright your lights are (which determines how much light energy is absorbed and converted to heat). You could also use heat lamps. Some people are building drying racks where they lay the prints and at the end of the day they turn on a set of fans and heaters (sort of like a huge film drying cabinet like the Jobo Mistral II for example). On timers of course.

There are lots of ways. But it's difficult to solve a problem if you can't first define it.

chris jordan
25-Jul-2006, 15:27
Bruce do you have any problem with the paper warping or wrinkling when you use the heat method?

QT Luong
25-Jul-2006, 17:09
To be safe, I use a combination of the hair dryer, dry in the open, and interleaving methods. The heating doesn't seem to make the paper flatness (or, more appropriately, lack thereof) worse.

Bruce Watson
26-Jul-2006, 06:32
Bruce do you have any problem with the paper warping or wrinkling when you use the heat method?
Not in the four years or so I've been doing it, with the limited number of stubstrates I use, no. I can't remember anyone else mentioning flatness issues either.

chris jordan
26-Jul-2006, 10:30
Okay then, as of this morning I have a new piece of equipment in my printing studio: My wife's hair dryer!