Soaking Psa Stamps & Linn's

I read the article in the recent edition of Linn's by Joe Brockert "Tough Choices Lead to Unsoakable Self-adhesive Stamps." I found this very informative; a good discussion of the layers, effect of printed vs unprinted areas, and so forth.

A while back I consulted the article in American Philatelist (October 2010) by Peter Butler "It's Like Magic - Removing Self-Adhesive Stamps from Paper." This was about Bestine, but also about Pure Citrus. While Pure Citrus is flammable, I consider it much safer than Bestine which contains heptane. In this article Dick Osman also used a credit card to carefully scrape the adhesive off the back of the stamp (instead of using powder.) I know that some people suggest leaving the paper on, and trimming as best you can.

I've experimented only a little with Pure Citrus, and it seems pretty good to me. I'm not sure whether all PSA stamps would release as well. But I can't see why not; the Pure Citrus is applied to the envelope side for a few seconds and the stamp releases along with the PSA. Whether the Pure Citrus might damage a certain stamp I'm not sure. There are certain stamps which are known to not play well with Bestine though.

I have mixed feelings about PSA stamps. I can understand the economics, and the convenience to users. And, printing technology has advanced, allowing designs unheard of before. But if I'm honest, I just prefer water-activated gum. And engraving too by the way. Anyone want to chime in on this topic? It's possible that the subject has been talked-out, but the Linn's article got me thinking about it again. To have soaking PSA as a cover story in 2021 shows me that there is interest in the topic...

Any of the articles discuss what happens in 15-20 (or more) years? Accelerated aging testing needs to be done on just the stamps with and without adhesive and also on stamps which have been 'treated' by amateur chemists.

In my opinion leave them alone (on paper). At least this approach only leaves a single variable; whether or not the adhesives, paper, and paper coatings (as issued) stand up to the passage of time. Adding in other potential factors, like exposing the stamp to various solvents, only increases the risks of the unknown. Future hobbyists should know more than we do today and stand a better chance at conservation.
Don

What is a PSA Stamp?

Pressure Sensitive Adhesive
Don

Thanks Don,
I googled, and was met by videos of Art Hobby Stamping.

Don, I don't recall anything about whether the stamps would hold up over time after exposure to various solvents - and it's a good point. Also, probably a good reason to leave them be. If stamps are to be mounted, Mystic (for one) suggests a slightly bigger mount to allow for added thickness. Makes for some mighty thick stamps I guess. Here are APS links, in case anyone needs them:

The 2010 article:
https://classic.stamps.org/userfile...es-Part1.pdf

Readers comments:
https://classic.stamps.org/userfile...es-Part2.pdf

I read the Linn's article, too, and I kept waiting for the author to explain why the US is so different from most of the rest of the world. The self adhesive stamps of Japan, for example, face all the same obstacles that US printers face, yet all of them are soakable, most of them coming off paper just as easily as stamps using water activated gum. Many other countries' PSA stamps are the same way. My guess is that it comes down to two things: 1) cost - the USPS doesn't want to pay a premium for soakable PSA stamps and 2) they simply don't want people collecting used stamps, since they don't gain any revenue from that.

I know the article was about US stamps, but additional context would have improved the article. The US is actually an outlier in how un-soakable the stamps are; I don't think most American collectors understand that.

TheArtfulHinger,

I didn't know that, but not really surprised. Not only does the USPS not want to, I suspect they simply can't, financially.

I'd be relaxed about this, and simply trim the paper around the stamp. After all, if you also collect mint stamps, you'll have mounted the self-adhesive and its original backing paper in your album. The main drawback seems to be with stamps stuck on material other than papef, eg a jiffy bag or cardboard.

I've tried the Pure Citrus method and found it too tedious for my taste. It's tough to get all the adhesive off, which means the leftover will stick to everything unless you apply powder of some sort, another possible contaminant. Even after I had the process down, and did a dozen stamps during the session, it took me about 10 minutes per stamp if one counts the cleanup time. Afterward, the room with the treated stamps smelled like oranges for weeks, not necessarily a bad thing, but a lingering reminder of the messy task.

For those of us who -- get ready to clutch your pearls -- hinge our stamps in albums, do you recommend just applying the hinge to the paper backing? Will the hinges be easily removed from the paper down the road?

I've pretty much decided not to even try soaking US PSAs off paper going forward. Life is too short for the aggravation.

In my very limited testing, I found that the PSA residue left on the stamp was removable using a plastic card - as described in the 2010 article, but using Pure Citrus, and eliminating the need for any powders. Will the stamps stand the test of time is a question though.

On hinging, there would be little more you could do than just hinge the back paper (envelope), and trim. Personally, I like using mounts, no matter the stamp. There's nothing "wrong" with hinging in my view. I did some tests however:

1. Hinging the back of USPS backing paper:
This is a shiny coated paper as we know. A hinge stuck, but I would say poorly. I'd be concerned that it would peel off in the album.

2. Hinging the back of envelope paper:
As expected, this works much better. Since regular paper will have more tooth than coated paper, the adhesion of the hinge is much better.

3. Hinging the back of a PSA stamp from which the PSA has been scraped:
The also work pretty well. A bit of a surprise there, since the back surface was very smooth, almost shiny. But the hinge seemed to adhere adequately.

I also collect current US used, and have been using Pure Citrus on
PSA stamps for over ten years. At this point, I have seen no evidence of any long term damage to the stamps. Time will tell if that changes.

Instead of a plastic edge, a second brief spray of Pure Citrus to the
back of the stamp after it has been removed from the paper allows the
remaining adhesive to be wiped off with paper towel.

I use this process for about 60 stamps per month, and have had no
problems whatsoever.

Green Machine, That is very good to know. 10 years is a pretty good time span.

Don, not the 15 or 20 years you mentioned, but 10 anyhow...

Some of us are removing moderns stamps with lighter fluid. Some are using citrous-solve. Some use other solvents. Some are leaving them on paper.

The next generation is going to be very happy with one of those decisions. And those stamps will carry a premium.

and...My guess is the used stamps that don't degrade will be nicer than the mint ones.