What's The Best Way To Clean A Classic Cover ?

I've had this Fitchburg railroad cover for a while.
It's seriously foxed.
Needs tender loving care.
Any thoughts about cleaning it ?

Those look more like scotch tape stains than foxing. Not a lot that can be done other than in the hands of a professional, especially with the other damage to the cover.

Those are tape stains not foxing. I think any attempt to remove the stains would be futile not to mention impractical.

Tape contains glue and glue contains the microorganisms that contribute to foxing.

Fungi of the Aspergillus group, that reside in gum and glue, are know to be tolerant to high osmotic pressure, wherein the diffusion of molecules through a semipermeable membrane from a place of higher concentration to a place of lower concentration becomes equal on both sides.

The rust pigment has been identified as a phenolic compound.

It's a thermosetting, hard, rigid brown resin produced by these fungi.

Foxing occurs most frequently in old stamps produced on low quality paper.

Thanks for the excellent information, Philatelist!

If it was just foxing, it would be easy to reverse. However, short of immersing this in carbon tet (don't, unless you have a death wish), you're not going to be able to remove the tape stains.

PS - if you know so much about tape stains and foxing, as you seem to imply from your post, why are you asking here for answers?

Now we just need Cliff Clavin to fill in the gaps...

I understand the effect, chipg. I haven't found a solution short of immersion in sodium chloride followed with subjecting the region of foxing to high levels of gamma rays. UV light increases foxing.

anyone have a spare cyclotron in their garage?

Unfortunately that is only true some of the time. Would that that were the whole story. To really identify the source of the problem we would need to know a lot more than you have told us about the nature of the tape, its adhesive, and the stains. Treating it all as "foxing" presupposes a particular chemistry which may or may not be operant here. Acting on the wrong diagnosis and applying the wrong "cure" for the problem could make the problem worse or do nothing at all. What have you tried and how did it do?

What can you tell us about the tape:
How long ago was the tape applied? Adhesives of the mid-nineteenth century were worlds apart from adhesives of the early to middle 20th century.
Was the adhesive on the tape rubber based?
Did it require additional moisture to activate it? Dennison Co. produced paper tapes in the late nineteenth century that were widely used by philatelists. These had the kind of gum (gum-Arabic?) adhesive to which you referred. However, these tapes did not leave the kind of stains we are seeing with this cover.

Maybe a combination of cloth tape and mucilage (fish glue) was involved?

If the culprit was an early cellophane tape, things can get really sticky (pardon the pun).

So can you fill us in and narrow the field a bit?

I will defer to the smarter more knowledgeable folk on the forum to discuss "best" for us.

The damage here goes w-a-y beyond foxing, and I will put forward a sacrilegious solution, under the assumption that the damaged sections have become as brittle as they are brown.



Cutting it down it will minimize the possibility that the chemical toning will not reach either the stamp or the cancel. It would also greatly reduce the area you may wish to clean/repair.

No... but I have two close by. Should I call and see if I can get on the schedule?

A Cliff Clavin reference. Nice one Sinclair.

All this technical jargon is making my brain itch.

So, if I understand this thread correctly, it would be easier to remove the cover from the tape stain than it would be to remove the tape stain from the cover?