It’s been a mainstay activity of the philatelist since the dawn of the adhesive stamp … the removal of used postage stamps from covers. Many of us will have commandeered the kitchen sink to soak our on-paper stock before peeling off the stamps and leaving to dry on a neighbouring work surface.
Traditionally, the gum applied to the back of the stamp was based on a water soluble chemical called Dextrin, produced by heating a starch. Indeed, the gum applied to the first stamps of Great Britain, sometimes referred to as ‘cement’, was derived from a mixture of potato starch, wheat starch and acacia gum. This process was effective as it only required a light application of water to activate the gum, traditionally by licking the stamp.
This simplicity was also a limitation. Water soluble gum can be easily activated in high humidity climates and this inevitably led to damaged stock in tropical climates. Its not too surprising that the first self adhesive stamps were introduced in Sierra Leone in 1964. Self adhesive stamps use an oil based gum, can be presented conveniently on waxed paper and are less susceptible to damage in high humidity environments. It took a while for the self adhesive stamps to be more widely adopted, not appearing in the US until 1974 and not until 1993 in the UK. Their adoption is now widespread and, with the recent pandemic in mind, it’s likely they will continue their domination in the interests of improved hygiene. The manufacturing processes are also more flexible, allowing for intricate die-cut shapes and less reliance on perforations.
However, it’s been a rude awakening for the philatelist who has discovered that the traditional method of soaking covers in water simply doesn’t work on self adhesive stamps. If you are one of the many who have attempted this, you’ll acknowledge that the most likely outcome is a severely damaged stamp. Some philatelists advocate soaking the stamp in hot water mixed with dishwasher soap. Generally, I would avoid soaking stamps in hot water as this is very likely to lead to staining (particularly those on coloured paper covers) or permanent damage.
Examples of early self adhesive stamps of Tonga and Sierra Leone
There are a number of products available with the required properties to break down an oil-based gum, including some that have been developed specifically with the philatelist in mind such as Lindner Stamp Remover. Non-aerosol citrus based air fresheners containing a natural hydrocarbon called Limonene have also proved effective. However, I have had most success with Bestine, a Heptene hydro-carbon based solvent. Bestine can be purchased from hardware stores or art stores, is particularly effective at removing self-adhesive stamps and in my experience, does not have any detrimental effect on the stamp.
Now at this point, I should include a health warning. Bestine and similar branded hydrocarbon solvents can be dangerous if misused. They are typically highly flammable and can be harmful or even fatal if swallowed. You should alway follow the instructions for use and always work in a well ventilated environment. I also prefer to use impermeable protective gloves and work over a disposable tray. Further, I decant the solvent into a small sealable bottle with a pipette (or eye-dropper) so that the solvent can be applied to the stamp with some accuracy.
Using the pipette, a few drops of the solvent can be applied around the perimeter of the stamp. This will be sufficient for the cover paper to become translucent and you will then be able to lift the stamp along the edges. Further solvent can be applied to the centre as the stamp is peeled from the surface using philatelic tweezers. You will note that the residue solvent evaporates rapidly.
So effective is this method that the stamp will often be removed with the gum still intact and almost no trace of the stamp remaining on the cover. If the gum has been retained on the stamp, it can then be mounted on an appropriate presentation surface or, as I tend to do, apply a little talcum powder or baby powder to the gum. This is enough to suppress the adhesive properties and the stamp can be stored in your collection as you would with any other used stamp.
In summary, solvents can be an effective way of removing self adhesive stamps from covers. However, please ensure that you follow the instructions for use and take the appropriate precautionary measures.