Paper Curling - Give your opinion on this

[ronmart]

Take a look at how much this paper curls. Nothing has been done to make the curl more dramatic - I simply dropped it to the ground and let it curl naturally.

Let's ignore what paper it is for a moment, for those experienced with paper and curling how would you classify this level of curling? (i.e., minor, normal, significant, massive, unacceptable, etc...)

For those who know me or know what this is, please do not say anything as I'm looking for unbiased opinions based on experience with paper curling.

And yes, I know about the D-Roller - the issue isn't what to do with the curling, but rather how acceptable is it to have this type of curling.

[Update] I’ll add that this is at the beginning of the roll.

Thanks!

[louoates]

I share your concern with curling. I had similar problems with Epson Enhanced Matte 44" roll stock especially when nearing the end of the roll. My supplier wasn't too helpful and I ended up using the paper anyway because most of the prints went to the framer and used with no problem. This was about a year ago. Since then Epson had changed the packaging of that paper somewhat and that greatly alleviated the problem. It still curls too much in my opinion but I like the paper very much and the curl doesn't affect the finished framed item.
There may be another issue that causes excess curling and that is storage temperatures. My supplier is in Arizona and product could be subject to very hot temps and very low humidity. I'm just guessing at this though. I'm interested to see any other explanations.

[ronmart]

I share your concern with curling. I had similar problems with Epson Enhanced Matte 44" roll stock especially when nearing the end of the roll. My supplier wasn't too helpful and I ended up using the paper anyway because most of the prints went to the framer and used with no problem. This was about a year ago. Since then Epson had changed the packaging of that paper somewhat and that greatly alleviated the problem. It still curls too much in my opinion but I like the paper very much and the curl doesn't affect the finished framed item.
There may be another issue that causes excess curling and that is storage temperatures. My supplier is in Arizona and product could be subject to very hot temps and very low humidity. I'm just guessing at this though. I'm interested to see any other explanations.

Good feedback - much appreciated!

My studio is on the warm side, but I'm in Seattle so it isn't excessive heat. Until recently there was no A/C and we tend to have dry summers, so perhaps this is a factor in the curling here.

FWIW, this curling has no impact on the image quality nor any head strike or scratching issues.

[louoates]

I looked at the d-roller site and learned that lack of humidity is a huge factor. I guess I should be keeping the opened rolls in the plastic bag provided.

[ronmart]

I looked at the d-roller site and learned that lack of humidity is a huge factor. I guess I should be keeping the opened rolls in the plastic bag provided.

Great feedback - thanks!

[jdoyle1713]

well Curl is curl.. whats acceptable is up to you..and how you deal with it..Alpha Cell papers Curl worse than Cotton ones.. Back coated papers curl less than non back coated papers.. with out know what paper it is I couldnt begin to explain why or what to do if anything..Humidity plays a major roll in curl.. Not enough and to much..again certain papers are better and worse.. I know this doesnt help much..but if you want to call me off line I will try and help if I can.

Cheers
Jim Doyle
Shades Of Paper

[ronmart]

well Curl is curl.. whats acceptable is up to you..and how you deal with it..Alpha Cell papers Curl worse than Cotton ones.. Back coated papers curl less than non back coated papers.. with out know what paper it is I couldnt begin to explain why or what to do if anything..Humidity plays a major roll in curl.. Not enough and to much..again certain papers are better and worse.. I know this doesnt help much..but if you want to call me off line I will try and help if I can.

Cheers
Jim Doyle
Shades Of Paper

Thanks Jim! I was talking to the guys at Canon and Red River about this and everyone is saying pretty much the same thing.

From what I'm gathering here, it seems that it's certainly a factor of the type of paper (which is Epson Exhibtion Fiber in this case) and the fact that we were having some reasonable heat (about 80 indoors due to an A/C part failure) and fairly low humidity.

I would still call this massive curl relative to all of the other roll papers I have (about , but at least I understand why now.

[jdoyle1713]

Well You got it.. Exhibition fiber is Alpha cell and doesnt have a backcoat..Its a tricy Paper for sure..But Images really well.. The D-roller doesnt work all the time on Alpha cell papers due to the structure of the paper base it will sometimes Crunch it and cause a crease..No easy solution I'm afraid.. If you have a Big drymount press it will do the trick

Cheers
Jim Doyle
Shades Of Paper

[MHMG]

The D-roller doesnt work all the time on Alpha cell papers due to the structure of the paper base it will sometimes Crunch it and cause a crease..No easy solution I'm afraid.. If you have a Big drymount press it will do the trick

Or, you can make your own version of the D-roller but use a larger diameter tube.  I uncurl papers with a home made de-curler made on a 6 inch diameter tube. It takes longer to remove the core set but is more gentle on the artwork. I leave the print on the tube for a few hours, and it gets the job done. 

Roll curl means that plastic deformation at the microstructural level has indeed taken place in the material. Wrapped around a tube, the media surface facing the tube side becomes compressed under pressure while the surface facing away from the tube becomes stretched under pressure. This leads to physical deformation of the material on the roll or what folks in the packaging industry typically call "core set".  The smaller the radius of the bend, the more extreme the mechanical stress levels become.  As this force is sustained hour after hour, day after day, the material begins to flow (i.e., plastic deformation) at the microstructural level to relieve the internal stress.  Also, moisture content in paper can vary by several percent of the paper's dry weight as paper goes from dry to humid conditions, and the "free" water in the paper acts as a plasticizer whereas chemically bound water adds to strength of the paper.  Moisture content (MC) in paper thus has well-known influences on the material properties of paper. Paper strength usually reaches a peak value when the paper is in equilibrium with approximately 40-45% RH environments (i.e. striking an optimum balance between bound water and free water within the paper fibers and the paper sizing agents).
 
The action of de-curling reverses the tensile stress direction in the media and thus induces further plastic deformation in the other direction.  De-curling is therefore not a benign process at all, because it once again causes physical voids and defects at the microstructural level, only in the opposite direction, and materials can tolerate only so much elongation and plastic deformation before they become visibly damaged.  As Jim noted, for example, if the mechanical stresses applied to the substrate by the de-curling tube exceed the substrate and/or coating's tear strength on the stretched side of the substrate, you get permanent and irreversible creases.  Using a larger tube diameter reduces the overall forces, so the "decurling" process will take longer but is more controlled and with less tendency to cause larger defects in the substrate.

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

[howardm]

as a non-roll user, it's a bit surprising to me that only a 'few hours' of de-curling seems to counteract most/all of the deformation due to weeks/months of curl from manufacture, distribution and sale.

[BobDavid]

I use a dry mount press to flatten curly prints. I got it reasonably cheap on ebay.

[jdoyle1713]

Mark

Thats the best answer I have ever seen.. You are the man!

Thanks for sharing all of the tech stuff.. Thats awesome!

Cheers
Jim Doyle
Shades Of Paper

[Ernst Dinkla]

as a non-roll user, it's a bit surprising to me that only a 'few hours' of de-curling seems to counteract most/all of the deformation due to weeks/months of curl from manufacture, distribution and sale.

Time has to be extended if the original paper has been stocked long, the core of the roll was 2", the paper thicker, the roll kept too long in a dry place and the decurling is done in a dry place or all together. I have used 6" rolls to decurl for ages now, occasionally I use a 3" core if the paper is thinner and with very thin papers I might go for a 1.5" core if in a hurry. The prints in the last case are not meant for eternity. I have always had my reservations about fast decurling in view of brittle coatings.


met vriendelijke groeten, Ernst

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[davidh202]

Mark beat me to it and was way more technical.
Same conditions exist when dry mounting prints on many substrates. Unless you put the finished mounted package under a uniform heavy weight ( I use a 3 x 5 sheet of 1/4" plate glass) the mounted side will usually bow upward due to shrinkage stress.
Many times counter (back mounting) with similar weighted materials will counteract that, but it is easieir to use weight untill the item cools or dries.