Self-Stick Stamps (Self-Adhesive Stamps)


Until very recently, almost all stamps printed from every country throughout the world came with adhesive gum on the back.  These traditional adhesive stamps are easy to lick or otherwise moisten, but the gum that's been used on stamps hasn't always been of the highest quality.  Throughout the years gum has been made from various plant products such as cornstarch, gum Arabic, sweet potatoes and sugar, and sometimes stamps fell off letters. 

The United States Post Office tried various experiments to improve the "stickiness" of the stamp gum used on United States stamps, inluding trying a special "summer gum" that was intended to resist high humidity and a special "winter gum" that was intended to resist cracking in cold, dry winter air.

The small South Pacific kingdom of Tonga came to the rescue.  Although the source was unlikely, being such a small and undeveloped country, the solution was brilliant.  Tonga printed the world's first self-adhesive stamps in the 1960s, including stamps that were appropriately shaped like bananas.  These stamps were so unusual, both for their novel self-sticking ability and their die-cut shapes, that they became a big hit with stamp collectors around the globe.  Since then, many countries have joined Tonga in printing self-adhesive stamps.  Peel-and-stick stamps are now the most common type of US stamps.