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Postage stamp gum

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The reverse of a stamp of the Allied Occupation of Germany.

In philately, gum is the substance applied to the back of a stamp to enable it to adhere to a letter or other mailed item. The term is generic, and applies both to traditional types such as gum arabic and to synthetic modern formulations. Gum is a matter of high importance in philately.

History

Before postage stamps existed, people receiving letters would have to pay for them. The payment was based on how many papers were in the envelope and how far the letter had traveled. Rowland Hill came up a solution of prepayment. This led to his invention of the stamp gum in 1837. The world's first adhesive postage stamp was called the Penny Black.[1][2] Many early stamps were not gummed, however, and some have been unable to be gummed due to shortages, for instance the typewritten Uganda Cowry stamps of 1895. Extreme tropical climates were also a problem for Curaçao and Suriname. Some stamps, intended only for sale to stamp collectors have been issued without gum, for instance the United States Farley's Follies souvenir sheets of 1933. On the first stamps of Great Britain the gum was called cement [3] and was made from a mixture of potato starch, wheat starch and acacia gum.[4]

Types and application

Originally, gumming took place after printing and before perforation, usually because the paper had to be damp for printing to work well, but in modern times most stamp printing is done dry on pre-gummed paper. There have been a couple of historical instances where stamps were regummed after being perforated, but these were unusual situations.

On early issues, gum was applied by hand, using a brush or roller, but in 1880 De La Rue came up with a machine gumming process using a printing press, and gum is now always applied by machine. The gum is universally spread as uniformly as possible.

The greatest manufacturing problem of the gumming process is its tendency to make the stamps curl, due to the different reaction of paper and gum to varying moisture levels. In the most extreme cases, the stamp will spontaneously roll up into a small tube. Various schemes have been tried, but the problem persists to this day. On Swiss stamps of the 1930s, Courvoisier used a gum-breaking machine that pressed a pattern of small squares into the gum, resulting in so-called grilled gum. Another scheme has been to slice the gum with knives after it has been applied. In some cases the gum solves the problem itself by becoming "crackly" when it dries.

The appearance of the gum varies with the type and method of application, and may range from nearly invisible to dark brown globs. Types of gum used on stamps include:

Some stamps have had gum applied in a pattern resembling a watermark, presumably as an additional security device. German stamps from 1921 had a pattern of wavy lines while Czech stamps from 1923 had gum showing the initials of the Czech Republic, CSP. These patterns have been called gum devices [4] or gum watermarks.[5]

Self-adhesive stamps

In recent years, the use of self-adhesive stamps, otherwise known as pressure-sensitive stamps, has become widespread. This relatively new form of stamps has a release carrier backing that has the same pressure-adhesive backing as the stamp itself. Therefore, the stamps can be released easily from the backing and placed onto a postal envelope.[6] The first use was by Sierra Leone in 1964,[7] and the United States tried it later on a 1974 Christmas stamp; this was judged a failure and was not reintroduced until 1989 when it gradually became widespread. In the 1990s, the U.S. Post Office began transitioning from water-based stamps into the use of self-adhesive stamps. By 1995, only 20 percent of the thirty-five billion stamps the Post Office produced every year were self-adhesive,[8] yet by 2013 almost all U. S. stamps issued had become self-adhesive. The rapid transition to almost all water-based stamps can be attributed to the United States Army during the Desert Storm, in which the soldiers could not properly send letters because their gum postage stamps would constantly curl or stick together.[9] Additionally, the famous television show Seinfeld played an episode in which a character died from licking envelopes, which unexpectedly created almost nationwide support to evolve gum stamps and envelopes to become self-adhesive.[9] Currently, the USPS is improving the quality of the self-adhesive stamp in order that they become more recycling compatible.[10] Traditional gum-based stamps are still being produced, yet mainly for the common hobby of stamp collecting. Additionally, all Israeli postage stamps feature a water-activated adhesive that is certified Kosher.

Health Risks

Negative publicity from the Sienfield incident was just one of the factors involved in comprehensive studies of the health risks of lickable stamps. A 1965 study showed that bacteria and viruses remained viable for months at a time on dried stamp gum, in fact, the study showed that populations of bacteria thrived in dried postage stamp gum.[11] The study tested E. coli and Staph. aureus bacteria on various gum samples, both plastic and dextrin based.[11] After having determined the extent of the growth and viability of these pathogens, the study concluded that because the manufacture of stamp gum was prone to contamination, and dried stamp gum provided a suitable environment for bacteria to thrive in, these lickable postage stamps constituted a significant threat to public safety.[11]

Philately

Multiple hinge remnants are visible on the back of this stamp.

For collectors, gum is mostly a problem. Im 1906, trouble had constantly arisen due to the gum on the under face of the stamps. There was an official notice that stated that stamps were going to be prepared with 'hard' gum, and were intended for use in the summer or humid season to prevent the premature sticking together of the stamps, or the sticking to the paraffin paper when in book form. It is rarely of use in differentiating between common and rare stamps, and being on the back of the stamp it is not usually visible. Nevertheless, many collectors of unused stamps want copies that are mint, never hinged which means that the gum must be pristine and intact, and they will pay a premium for these. While not so much of a problem for modern issues, the traditional way of mounting stamps in an album was with the use of stamp hinges, and some experts claim that very few unused stamps from the 19th century have not been hinged at some point in their existence. This means that old unused stamps are inevitably under suspicion of having been regummed, and the detection of regummed stamps is an important part of philatelic expertisation. In 1913, a famous stamp called the Clermont steamer had an adhesive that was inscribed; "Hudson-Fulton Celebration". Stamps that had words inscribed on the adhesive were of even more interest to philatelists who made a special point of collecting picture stamps.

However, it has always been desirable for the dedicated philatelist to maintain the integrity of the backing gum, and many collectors take great pains to remove any paper residue that has collected on the gum without removing the gum itself.[12] Such stamps were considered more desirable than stamps without their backing gum.

Stamps printed on the gummed side by mistake have become valuable varieties.

References

  1. ^ "Rowland Hill's Postal Reform".
  2. ^ "History of Stamps".
  3. ^ Williams, L.N. & M. Fundamentals of Philately. State College: The American Philatelic Society, 1971, p.494.
  4. ^ a b Mackay, James. Philatelic Terms Illustrated. 4th edition. London: Stanley Gibbons, 2003, p.65. ISBN 0-85259-557-3.
  5. ^ Patrick, Douglas & Mary. The Hodder Stamp Dictionary. London: Hodder & Stoughton, 1973, p.105. ISBN 0-340-17183-9.
  6. ^ Gray, Robert. United States Patent, US5685570. Blackburn South, 1997, p. 4
  7. ^ Williams, p.500.
  8. ^ Grossman, Anne Jane. Obsolete: An Encyclopedia of Once-Common Things Passing Us By. Abrams Image, 2009.
  9. ^ a b Grossman
  10. ^ Recyclable, Compostable Stamps that Last “Forever”. Volume 11 Issue 12. Forest Products Laboratory's Newsline, 2012, p. 1
  11. ^ a b c S. Selwyn (1965). The transmission of bacteria and viruses on gummed paper. Journal of Hygiene, 63, pp 411-416. doi:10.1017/S0022172400045290.
  12. ^ Johnson, Stanley C. The Stamp Collector. [S.l.]: Herbert Jenkins, 1920. Print.
  • Bells, Mary. “History of Stamps.” About. Web. 20 October 2013.
  • “History of Stamps.” The American Philatelic Society. Web. 20 October 2013.
  • Johnson, Stanley Currie. The Stamp Collector: A Guide to the World’s Postage Stamps. H. Jenkins Limited. 1920. p 24.
  • Poole, Bertram. The Standard Philatelic Dictionary. Beverly, Mass.: Severn-Wylie- Jewett Co., 1922. Print
  • Sutton, Richard. The Stamp Collector’s Encyclopaedia. New York: Philosophical Library, 1966. Print.
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