Paper Curl / Digital print

[Kees]

Hello,
I am looking for a type of paper that, after printing and finishing, will not curl, or as little as possible. The problem of curling /warping arises not by printing but over time, for example after 1 week/month. Because the product is in use for a long time it must remain as flat as possible. The paper I'm looking for can be up to 310 mu thick, and ca. 300 gr, the product itself is ca. 125x225 mm. It might be possible that there is no paper that does not curl / warp over time? Printing on plastic is not an option (to expensive), just plain digital printing, also no laminate, job has to be done on a Ricoh Pro C901. Paper tested so far are: Invercote Creato, OMNIsilk ni, Color Copy, core silk. Thank you for replying!

[Emtri]

Have you tried swapping grain direction or lowering the fuser temp? (I've never run a Ricoh machine)
You may not be able to get away with no curl. The nature of digital is applying heat to the paper, which can cause curl.
What exactly is the end application of what your trying to do here? normally a slight curl isnt an issue.

[Kees]

Tanks for your reply Emti,
First, the end application is a so called "Backcard", this is a card that comes in a "card spinner" and we print our logo, articlenumber or design on it. This card stay's in the spinner for a long time. As long as there are greetingcards in the spinner the backcard has some support and will nog curl that much, only the part sticking out at the top.
We print these backcards in offset (not ourselves) on Carta Solida 295 gram or Mat Creato 350 gram. Printing in offset is cost effective when we print a lot of these things but we sometimes export small quantities to Germany or France and in full colour offset this is very expensive, so digital printing is interesting since we have a nice printer and finishing equipment in house. The curling does not happen immediately, but gradually, under the influence of environmental factors such as heat/cold and humidity. Changing the grain direction is not possible because the backcard has to stand upright, lowering fuser temp is also not an option because curl does not happen while printing (I think, I'm not a printer). So, as you say, I may not be able to get away with no curl.