Un-backing a Poster from Linen

[erik1925]

There has been some discussion in another thread about the un-backing of posters from linen, if one might choose to. Rather than divert bruce's thread, it seemed like a good question to ask. All restorers maintain that the work they do is reversible and that the materials they use, unless asked otherwise by a client, are water based (the wheat starch adhesive, water color pencils, and paints used to touch up or airbrush borders with etc).

But what IS the process, if someone wants to have a poster removed from a backing? One cannot just go and have the poster floated from the linen, washed of the adhesive, and set if off to dry. It would curl, warp, get wavy, or worse. (And I'm referring here to newer rolled posters, like the Star Wars posters, as have been discussed a bit, as well as ones that didn't have any restoration or paper fills, repairs etc).

Once removed from the linen and washed of the adhesive residue, could pressing alone bring the poster back closely to what it once was? Or would more need to be done to it, as well? Would a (gel-type) backing or sizing agent need to be applied to help it hold its original shape?

[Dread_Pirate_Mel]

I've pulled the linen off a couple of my not-so-valuable posters.  The linen comes off cleanly and the poster remains somewhat rigid.

[erik1925]

Was this done without water? With you just carefully peeling the linen and masa paper away from the back of the poster? The rigidity may be due to the wheat paste adhesive residue left on the back of the poster.

[MoviePosterBid.com]

I was just waiting for someone to post a thread on the subject after I read the other comment

linenbacking could be reversed

is an incorrect statement

the correct is "any item can be removed from the linen" however, the process cannot be "reversed"

the poster has already been submerged for instance and needs to be submerged again to remove it. The paper will never revert back to it's unrestored state

in general, the only reason to remove a linenbacked item is to re-back it again, better than it was the first time

[erik1925]

Technically, a poster can be floated off its linen backing and "reversed." True enough... But the poster paper is NOT the same, structurally, as it was, prior to backing. Being submerged and saturated initially, will forever change the way the paper behaves.

I would like to see any poster, removed from linen, washed of the wheat starch adhesive residue, and left in a corner to dry. I think it would look rather interesting.

I would think pressing it with weights (and between boards and blotter paper), would be needed, minimally.

[CSM]

I've pulled the linen off a couple of my not-so-valuable posters.  The linen comes off cleanly and the poster remains somewhat rigid.

What?  Why?

[Dread_Pirate_Mel]

What?  Why?

Because I felt like it.

[110x75]

Sell them to T now, he'll love them! 

[CSM]

Because I felt like it.

Without any soluble medium?  Sounds like very poor backing jobs to be able to do that...

[Charlie]

Technically, a poster can be floated off its linen backing and "reversed." True enough... But the poster paper is NOT the same, structurally, as it was, prior to backing. Being submerged and saturated initially, will forever change the way the paper behaves.

Have to chime in.  If the poster is just wet, it doesn't change structurally.  What happens is that parts of the poster dry at different rates (random evaporation and slightly different thickness perhaps) and there is expansion and shrinking which causes the poster to wrinkle. The non-uniform expansion and contraction causes internal stresses that can weaken the paper perhaps.  It the poster was dried uniformly after being wet, while held flat, it would be the same poster.  PM uses a heat press.  There was a blog entry on a THEM US OS.  They washed it and then heat pressed the poster and folded it back up.  Inks could be a different story and clay based inks another.  Paper no.

For example, paper is made by a pulp solution being sprayed uniformly onto a support and then dried uniformly...  It's the support and uniform drying that makes it flat.

However, if you place chemicals such as bleach this can weaken the poster and make it more brittle.  If you handle the poster too much while it is wet the stress can weaken the poster. 

With removing linen, the problem is in not knowing what was done before. Removal is also very stressful IMO on the paper.  It doesn't just float off.  You soak it for hours and still end up separating the layers.  I think you can remove the linen first but that requires a temporary support using the front of the poster.

Backing IMO is reversible (linenbacked to just poster) but not desirable or proper.  There should have been a reason it was backed.  It will most likely have seen unusual stresses during both processes and be weaker and more fragile.

Plus most restorers don't even use fully/easily reversible mediums for touch up work.  Sure they are suppose to float off - would love to see that. May have to try it at some point.  Colored pencil doesn't float off.  Acrylic paint doesn't just float off. What do you think is on that T-shirt you like? (I exaggerate - but it paints the picture.)  It's all a sales pitch.  You need to know what you want and prescribe it to your restorer.  However you will most likely get talked out of it because it is not to their advantage.

[Ari]

Point is, you have a crisp machine folded poster that's gets linen backed, you can NEVER reverse it to being a crips factory folded poster again.

[erik1925]

+1

Even though a poster can be un-backed (and then not re-backed), pressing and/or gel backing it would be necessary to keep it lying flat, and not becoming rippled or wavy.

Any poster is never the same as it was prior to it being backed. (Again, in the context of this thread, I'm referring to rolled, pristine posters that require no color touch ups or other repairs, prior to backing, or not posters that have been removed from an old backing and placed on new).

[paul waines]

Because I felt like it.

 

This is one of the best posts I've seen for a while on here, nice one Mel.

It's our own stuff and we can do as we please...

[joemustang65]

+1

Again, in the context of this thread, I'm referring to rolled, pristine posters that require no color touch ups or other repairs, prior to backing, or not posters that have been removed from an old backing and placed on new).

Why would you LB a pristine poster? IMO a waiste of time and money to LB a pristine poster.

Erik , as Charlie says if you let them dry uniformly the poster would be pretty flat and not wavy.
Just do a little test yourself , pick a cheap folded poster, put in on holytex (or plastic so that it doesn't stick to your table and spray it soaking wet, then cover it with holytex (or plastic) and let it dry slowly, you will be surprised of the result, fold lines will be less visible , partly gone due to the weight of the paper itself)