Outgas problem........and Prints with waves/ripples

[edt]

I've had the 7900 for 9 months. Printed on several papers but mostly on Epson Premium Lustre. Mostly printing youth sports photos and posters, some portraits.

Recently I matted and framed an 18x24 print on Epson Lustre (behind glass). The print had air dried for about a week prior to framing. I never covered the print with plain paper to absorb the solvents, just let it air dry for 7-9 days. Makes me wonder how many other prints I've sold--framed by others-- might be having the same problem.

After 10 days behind glass there was already significant fogging from the outgas--and that was with the mat separating the print from the glass.

I'm about to do a project of about 25 framed prints where the prints will be in direct contact with the glass--they are football posters, printed with digital mats to keep costs down.

     Question 1-----Would the risk of outgas be a lot less if I use a mat surface paper rather than Epson Prem Lustre?

     Question 2-----Am I to believe that large production houses who keep these printers busy making large prints are going through the drill I keep reading about--on every single print? (cover print with plain paper for 24 hours, then cover with new sheet of plain paper for 24 hours, then let air dry for 5 days.......) Something like that might work for hobbyists, but production houses??

     Question 3-----Is there any better procedure to prevent outgassing other than the above process?

"What does M. R. do?"

I need to put this issue behind me once and for all. "Do everything on canvas" or "frame your prints naked" (without glass) are not options......thx for your help.

Ed T

[Alan Goldhammer]

I've never seen outgassing after that length of time.  I don't print on that particular paper but do print on Ilford Gold Fibre Silk and Museo Silver Rag.  I've framed prints after 48 hours of drying time (with an overmat under plexi) and not observed any problems.  I routinely put a cover sheet over the print and because of limited work room space stack prints on top of one another (usually 4-5 max; 13x19 from an Epson 3880).  Edit added-you asked about matte paper.  I suspect that it would not be an issue with matte paper because of the absorbent nature of the coating surface but you would also lose gamut.

Alan

[williamrohr]

I have written about this before ... we have seen it occur even after 6 months.  It seems to be related to ethylene glycol or very similar solvent (see prior posts) in particularly the black inks.  At normal room temperatures the vapor pressure of the solvent is very low and outgassing is VERY slow.  When you put the print behind glass the temperature rises particularly if there is any sunlight around (we have measured over 200 degrees with a special pyrometer) at which point the vapor pressure is much higher and outgassing occurs much more rapidly.  The only way we have tamed it somewhat for people who want the prints on Luster is to dry the print in a dry mounting press beneath sheets of phototex or similar absorbent paper (using very little pressure) at 200 degrees F multiple times until new paper stops absorbing the solvent (easy to see) and then coating the print with one of the Epson approved sealants.  Generally, we just avoid using it.   Bill

[feppe]

I have written about this before ... we have seen it occur even after 6 months.  It seems to be related to ethylene glycol or very similar solvent (see prior posts) in particularly the black inks.  At normal room temperatures the vapor pressure of the solvent is very low and outgassing is VERY slow.  When you put the print behind glass the temperature rises particularly if there is any sunlight around (we have measured over 200 degrees with a special pyrometer) at which point the vapor pressure is much higher and outgassing occurs much more rapidly.  The only way we have tamed it somewhat for people who want the prints on Luster is to dry the print in a dry mounting press beneath sheets of phototex or similar absorbent paper (using very little pressure) at 200 degrees F multiple times until new paper stops absorbing the solvent (easy to see) and then coating the print with one of the Epson approved sealants.  Generally, we just avoid using it.   Bill

Are these levels of outgassing problems unique to the Epson paper and/or Epson inks?

[edt]

I THINK everyone agrees that Prem. Lustre and similar papers with plastic layers that slow the drying process are the worst offenders. If black inks make the problem worse then that is an aggravating factor for me since a lot of my work is shot at night in lighted stadiums where the backgrounds are dark. (I'm a photographer) I am quite willing to switch another paper that has a D max that approaches the lustre, plus a lot of prints get framed behind glass anyway (hard to tell the difference.
But even if I do switch papers I still need to have a procedure to prevent outgassing that I can have confidence in.

I'm beginning to think that no production printer is using Prem. lustre or similar...probably due to the outgassing that is worse on RC papers.

[Wayne Fox]

I THINK everyone agrees that Prem. Lustre and similar papers with plastic layers that slow the drying process are the worst offenders. If black inks make the problem worse then that is an aggravating factor for me since a lot of my work is shot at night in lighted stadiums where the backgrounds are dark. (I'm a photographer) I am quite willing to switch another paper that has a D max that approaches the lustre, plus a lot of prints get framed behind glass anyway (hard to tell the difference.
But even if I do switch papers I still need to have a procedure to prevent outgassing that I can have confidence in.

I'm beginning to think that no production printer is using Prem. lustre or similar...probably due to the outgassing that is worse on RC papers.

We produce and frame a lot of work and many customers choose the Epson Luster.  We don't take any real precautions other than allowing about a day with the print uncovered.  I've never seen a problem with a print as bad as you describe especially that quickly ... it is very rare when someone brings one back with this problem.  I've never seen the issue at all with a non RC paper.

I don't think it's the black ink itself that's the problem, just that you have to lay down a lot of ink to get a good black, so more ink to outgas.  I don't think it's an Epson only issue, and I know my daughter had a print framed that I printed with an ipf6100 that had a problem.

Your experience does sound strange.  Are you in a fairly humid climate by chance?

[edt]

Wayne,
As to your question about humid environment--yes it's humid in Atlanta in the summer, but it's air conditioned inside so hard to tell...

I probably made a mistake in titling this thread, I should have titled it "Outgas AND Ripples/Waves problem." One way or the other I will come to grips with the outgas issue, but my other issue is matted prints "throwing waves." I've seen this happen with prints that were C print photos from pro labs and from Epson Prem. Lustre that I printed...both on matted prints and prints that were in direct contact with the glass.

fwiw i stopped by a gallery at lunch today--they had several Vincent Laforet photos framed under glass, approximately 40x60. They were not certain but they speculated (and they are likely correct) that the prints are not dry mounted--yet the prints showed almost zero "waviness." My guess is that the prints were printed on a heavier non RC papers, like an Epson Exhibition Fiber (flat and "boardy") or perhaps a mat surface paper without the plastic layer that is in the RC papers. If I can solve the waves/ripple issue by choosing a heavier more expensive paper that could still be less expensive than dry mounting almost everything--which is apparently the only way I can be sure the lustre will not ripple.....

[Sven W]

I recommend my customers to dry- or facmount prints larger than 24x30". Because of the gravity effect downwards. Even if a matte is used.
A few cases with textured fineart papers, it worked with direct contact with the glass. But it's not what
a museum conservator would suggest. 

/Sven

[edt]

Well, I like the idea of being "in compliance" regarding archival standards.......but the honest truth is the photography my customers buy from me is NOT fine are.....the prints CAN be replaced if necessary. I just purchased a used 500T-X yesterday so until I discover better procedures I will be dry mounting most things before framing. Don't want to see any more rippled prints.

[Alan Goldhammer]

With a 3880 printer, I'm not able to print the size prints you are discussing. I am curious whether hinge mounting coupled with an overmat will help prevent the rippling.  One might need several hinges at the top for very large prints coupled with a sufficient border around the print.

[Bruce Watson]

It's the nature of the ink. The pigment carrier is mostly water. But water alone won't do what needs to be done to prevent clogging of the print heads, etc. So, they add various glycols and glycerines. As noted in a previous post, at room temperatures these additives have very low vapor pressures and thus make the transition from liquid to vapor very slowly.

The idea that somehow a sheet of paper over the print is going to "absorb" these compounds is, well, laughable. Not going to help, as you have found out.

The only things that help speed the process of driving off these compounds are heat, and air movement. Heat to supply the energy to make the phase change from liquid to vapor, and air movement to blow the vapor away from the print so it doesn't just reabsorb what you are trying to get rid of.

One way to accomplish this (and there are doubtless many methods that will work) is with a hand held hair dryer. Low heat, high fan. Hold the dryer in one hand and support the print with the other. The hand holding the print can feel the changes -- at first the print will get slightly colder and feel damp, then it will experience a rapid warm up. When this happens, move to another area of the print. Repeat until done. BTW, you can smell the glycols coming off the print so there's no doubt what's happening.

Using this hair dryer method I've gone from printer to framed and on the wall in 45 minutes. These prints don't out-gas. Even in the sun. Even the black areas.

OTOH, I've got a large print on Photorag  (cotton rag matte surface) that still out-gasses after five years. I'm just too lazy to a) move it to a location where it gets zero sun, or b) to tear down the framing and process the print to get the contaminates out, or c) interrupt this "experiment" to see what bad things happen to the print over the long term because of the out-gassing (so far, nothing at all visible).

Finally, I've had prints, again on HPR, that were in the frames out-gassing, that I've gone through the trouble of tearing down the frame, drying the print, and reframing. Every time I've done this it's solved the out-gassing problem. So I know it works.

[John R Smith]

Bruce has got the problem analysed and solved. But if you are not in a rush -

On the wall of my studio I have a large pinboard. Every finished print goes up on the wall, supported by map-pins, and stays there for at least two weeks before it either gets sleeved in my storage albums or gets framed. Using the Epson K3 inkset, I have so far never had an out-gassing problem.

John

[narikin]

I do the same as Bruce - the hairdryer thing.
Non RC prints do seem better as the glycols can escape into the paper and out the back...

Some people may not notice this as their framer will dry mount (with heat) and then hold the work that way a few days while the frame is prepared. Accidentally this is the right amount of time to outgass!

 

[Brian Gilkes]

I'm printing out of Epson printers. Mostly heavy papers,coated and uncoated,semi-gloss to handmade .  Prints coming off are pinned to foam boards, and allowed to dry 24 hrs to a week. The former time is more often by necessity. In warm, dry weather this is usually sufficient. In cool weather I place oscillating room heater (that incorporates a dust filter) at the base of the print. After drying all prints are sprayed , mainly for UV protection. The drying regime seems to get rid of the glycols. Rippling may occur on just about any large print with a heavy, usually black ink-load. They just take longer, but they do naturally flatten.
If possible keep room temperature around 20-22deg C, humidity 40-50%. Lower humidity helps out gassing and ink drying, but results in more nozzle blocks.
A corollary of extended drying is that inks don't scuff or scratch as easily.  This one deserves a whole other thread!
Cheers,
Brian
www.pharoseditions.com.au

[Wayne Fox]

The idea that somehow a sheet of paper over the print is going to "absorb" these compounds is, well, laughable. Not going to help, as you have found out.

If you stack several prints interleaved with paper, in a day or so those papers are usually warped and full of ripples. They certainly absorbed something from the ink.  That being said I would agree that the paper most likely isn't absorbing enough to solve the problem.

[Alan Goldhammer]

As a chemist I'm interested in the composition of the K3 ink sets.  One can obtain the material data safety sheets for the inks pretty easily and one example is here:  http://files.support.epson.com/pdf/msds/t543100.pdf with the composition as follows (%by weight):
Carbon Black <3%
Proprietary dyes and pigments <5%
Proprietary organic materials 5-10%
Glycerols 15-20%
Water remainder

The level of glycerols (we don't know if this is pure glycerine or not though I think it unlikely) in the ink only marginally shifts the vapor pressure curve relative to pure water from a mixture perspective.  What we don't know if the nature of the other organic materials in the ink (whether they are solvents with a decent vapor pressure or not since this would have an impact on outgassing).  The vapor pressure of pure glycerin is very low at normal temperatures relative to water, and even using a hair dryer is likely not to raise the temperature high enough to have a measurable effect on the vapor pressure, thus I don't think that the level of glycerols will change much (some will come off with the water but there should be residual glycerol left).  I don't know what the surface temperature of a framed print in direct sunlight is but suspect it would have to be quite high for glycerol outgassing following drying.  The chemistry of all this is quite complex (with the caveat that it's been a lot of years since I took physical chemistry so you can take all of this with a grain of salt if you wish).

[Ernst Dinkla]

The level of glycerols (we don't know if this is pure glycerine or not though I think it unlikely) in the ink only marginally shifts the vapor pressure curve relative to pure water from a mixture perspective.  What we don't know if the nature of the other organic materials in the ink (whether they are solvents with a decent vapor pressure or not since this would have an impact on outgassing).  The vapor pressure of pure glycerin is very low at normal temperatures relative to water, and even using a hair dryer is likely not to raise the temperature high enough to have a measurable effect on the vapor pressure, thus I don't think that the level of glycerols will change much (some will come off with the water but there should be residual glycerol left).  I don't know what the surface temperature of a framed print in direct sunlight is but suspect it would have to be quite high for glycerol outgassing following drying.  The chemistry of all this is quite complex (with the caveat that it's been a lot of years since I took physical chemistry so you can take all of this with a grain of salt if you wish).

Reversed image building on the glass has been reported in the past. A black area of a print will get hot in the sun or halogen spots and with a minimal distance to the relative cold glass in front of it there will not be enough air convection to transport the glycerol to other spots. The glycerol carrier could also be glycol or water that might spread and be absorbed again at night while the glycerol condensates immediately at the glass in front. Static properties involved as well? Glycols can be used in inks as a retarder, even in water based inks. The evaporation speed can vary quite unexpectedly with mixes of solvents if one goes the properties of the single components alone. That is what I have learned of an article on silkscreen inks. If glycols and water are already evaporated before framing I think there is little chance that the glycerol on its own can cross the distance.


met vriendelijke groeten, Ernst Dinkla

spectral plots of +100 inkjet papers:
http://www.pigment-print.com/spectralplots/spectrumviz_1.htm

[MHMG]

The vapor pressure of pure glycerin is very low at normal temperatures relative to water, and even using a hair dryer is likely not to raise the temperature high enough to have a measurable effect on the vapor pressure, thus I don't think that the level of glycerols will change much (some will come off with the water but there should be residual glycerol left).

And there are actually two factors involved in this residue on cover glass phenomenon, one being the off-gassing, the other being continued diffusion (laterally and vertically) of the solvents into the media. The RC papers largely prevent the diffusion of the glycol into the paper core, but some manufacturers also deliberately add a subbing layer below the top coat ink receptor layer and the Polyethylene layer to deliberately serve as a reservoir for the solvent load (with additional chemistry in that subbing layer for this purpose). Given that the vapor pressure is high as Alan noted, I suspect the hair dryer technique does a helpful job promoting the continued diffusion of the ink solvents deeper into the media rather than actual glycol removal through evaporation. That in turn ties up more of the solvent so that it won't end up as easily on the glass, and hence the paper appears to be drier. As for the paper "wicking" method of reducing the off-gassing, I know many people swear by that method, but as a scientist, I'm very hard pressed to come up with a reason why it would promote glycol removal from the printed sheet any faster than air drying. It could be diffusion related, but that means a very good contact would have to be established.  Curious...indeed.

Mark
http://www.aardenburg-imaging.com

[Ernst Dinkla]

Given that the vapor pressure is high as Alan noted, I suspect the hair dryer technique does a helpful job promoting the continued diffusion of the ink solvents deeper into the media rather than actual glycol removal through evaporation. That in turn ties up more of the solvent so that it won't end up as easily on the glass, and hence the paper appears to be drier. As for the paper "wicking" method of reducing the off-gassing, I know many people swear by that method, but as a scientist, I'm very hard pressed to come up with a reason why it would promote glycol removal from the printed sheet any faster than air drying. It could be diffusion related, but that means a very good contact would have to be established.  Curious...indeed.

Mark
http://www.aardenburg-imaging.com

With silkscreen printing of solvent inks the heated air dryer is usually of the pulsed type, air jets placed in a grid so an area gets repeated changes in air pressure and the solvents are more or less pulled out. A laminary air flow isn't effective. Solvents of a second or third printrun can diffuse in the first ink layers as well which can give the wrong impression that the inks are dried enough. So drying fast after printing thin layers is a much better method than thick ink layers in a slow drying process. With (eco)solvent inkjet printers the (vinyl) media is often heated before and after the printheads area, hot plates etc. It creates a better bond but also gives faster drying.

If the absorbing sheet on top does more or less what the glass does, catching the glycerol, then there's a good chance that the water + glycol go through that paper membrane and disappear in thin air and are no longer able to transfer the glycerol.  If the print is in contact with/on top of a rechaud, hot plate, it could speed up that process with a better chance to take out more glycerol. I guess the same hot plate underneath and a moving air jet in front would have a similar effect, glycerol then condensating on the cool parts of the studio :-)


met vriendelijke groeten, Ernst Dinkla

Dinkla Gallery Canvas Wrap Actions for Photoshop
http://www.pigment-print.com/dinklacanvaswraps/index.html

[Alan Goldhammer]

Good comments from Mark and Ernst.  It's hard finding vapor pressure data for the temperatures that prints are stored at so one cannot be totally accurate in calculating the residual glycerol in prints.  Air drying, irrespective of temperature, will lead to vaporization of a mixture of water/glycerine where the relative concentrations are dependent upon the vapor pressures of the two components.  Thus, what is coming off the print is a mixture of the two but not in equal amounts.  I suspect that there will always be some trace amounts of glycerine in the print but probably too small to off gas as the moisture content of the print will now be in equilibrium with the surrounding environment.  Placing a sheet of paper over the print will lead more to diffusion and subsequent absorbance of the excess water/glycerine.  I doubt that it migrates and then evaporates into the room, so Ernst doesn't need to worry about the walls being a repository for the glycerine.  In addition, one would obviously expect matte and RC papers to behave quite differently (it would be interesting to find out from others whether rag based glossy papers exhibit the same type of gassing phenomena as the RC papers do).  I'll see if I can track down some vapor pressure data and see if a sample calculation can be done.