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Harriet Tubman, the Old Hickory and the remaking of $20 Bill
Posted on December 27th, 2016 by Dr. Sina Ebnesajjad in Chemical Manufacturing Excellence
Young Sofia B. wrote a letter to President Obama. It said that it would be a very good idea to put a woman on a dollar bill. She wrote that there are not a lot of women on dollar coins or bills. She made a list of women who should be on a coin/bill including Rosa Parks, Michelle Obama, Hillary Clinton, Betsy Ross, Harriet Tubman, Ida Wells, Anne Hutchinson, and more. President Obama mentioned the letter at an appearance in Kansas City, Mo. “And then she gave me like a long list of possible women to put on our dollar bills and quarters and stuff, which I thought was a pretty good idea,” President Obama said.
The deed is now done: beginning in 2020 Harriet Tubman will replace Andrew Jackson (aka, the Old Hickory) on the $20 bill. The old hickory will not disappear entirely from the bill: he will appear on the back, next to the image of the White House. Born a slave in 1820 in Maryland, Tubman managed to escape while in her 20’s. She then dedicated her life to helping others achieve their freedom through the Underground Railroad, a system of safe houses and abolitionists. Harriet’s journey has now been completed in a place of distinction with Presidents Lincoln and Washington and Benjamin Franklin and others.
How are we going to keep Harriet Tubman on the bill? More specifically how is money made to endure so long while preventing it from being counterfeited? There is a lot more science and technology to producing bills than one might expect. Considering over a trillion US dollars is in circulation around the world, endurance and anti-counterfeiting measures are well justified. US dollar is simply the de facto currency of the globe. That is a long way from the times when each US state produced its own currency.
Making the Money
United States notes are made from cotton fiber paper. This is a special type of paper unlike any other one that is actually made of wood fiber. The United States Bureau of Engraving and Printing (BEP) designs and produces a variety of security products including dollar bills. As the US Government’s only source of paper currency production, the Bureau prints billions of Federal Reserve Notes for delivery to the Federal Reserve System each year.
Technology has brought the BEP a long way to a state-of-the-art manufacturing operation producing U.S. paper currency. The production of this currency is not an easy or simple task, but one that involves highly trained and skilled craftspeople, specialized equipment, and a combination of traditional old world printing techniques merged with sophisticated, cutting edge technology. Overall, there are numerous, distinctive steps required in the production process.
The notes have been redesigned to retain the same size as previous notes and use similar portraits and historical images to maintain an American look and feel. Security features maintained in the enhanced Federal Reserve notes include a portrait watermark visible when held up to a light, two numeric watermarks on the $5s, an enhanced security thread that glows under an ultraviolet light, micro printing, improved color shifting ink that changes color when the note is tilted, and on the newly redesigned $100 notes, a 3-D security ribbon and enhanced, raised printing.
Various types of inks are used to produce each banknote, such as optically variable ink that changes color as the note is tilted, as well as ink that reacts in near-infrared light. Color control and rheology (the flow of ink) become critically important when printing this type of security document; therefore the process can be incredibly complex. The US cotton notes are soil-resistant, chemical-resistant and durable.
The Bureau of Engraving and Printing’s paper has been sourced from the same company (Crane and Company) since 1879. It consists of 75% cotton and 25% linen blend. There are fluorescent security threads, watermarks and red and blue fibers embedded in the paper at the time of manufacturing. Consistent color and feel of the paper is critical to the success of the notes over multiple runs. The fibers of the paper have been super calendered (flattened) to increase smoothness. There are three main printing processes used to produce US banknotes: offset lithography, intaglio and letterpress.
In the first pass the notes are printed on an offset lithographic KBA Simultan press, where the face and back of the note are printed simultaneously. This sheet-fed press is capable of printing 8 colors on each side. The sheets are then left to dry in storage for 72 hours before moving to the intaglio process. The backs of the notes are printed first using engraved plates to achieve tactility. Only since 2004 has the engraving process become digital, a change from the past when all plates were hand-engraved.
The new process uses a plastic mold and assembly process for making a full step and repeat master die through heat and pressure. This plastic master is treated with a light coating (conductive agent) and placed into a nickel bath for 14-16 hours where the nickel “grows” or adheres to the plastic master. The BEP has some of the last siderographers in the world, and these individuals bring together each individual intaglio engraving onto a master plate and correct for imperfections. The Bureau has two intaglio presses, including an Intaglio 10 Press, which uses a direct inking system and can produce 8,000 sheets per hour. The second intaglio press is called the Super Orloff, which has an indirect inking system of plate to blanket to engraving.
The next step in the process is to print the face of the notes using an intaglio press, whereby finely engraved line work acts as a security feature by introducing a three-dimensional tactile element called a “rumble strip”. Lastly, the notes are trimmed for the Currency Overprinting Processing Equipment (COPE), which is a letterpress that applies serial numbers and seals. Only after this step are the notes considered legal currency. The sheets are then trimmed down into single notes and packaged.
Canadian banknotes have seen massive make overs in the last 40 years, ranging from color printing in the 1970’s to color-shifting ink in the 1980’s to security features embedded in the notes in the 2000’s. The recent banknote series features an impressive innovation: a new polymer substrate instead of paper. Polymer has allowed the Bank of Canada to stay one step ahead of counterfeiters by embedding high-tech security features right into the thin plastic film in a way that could never be done with cotton paper notes. Over 30 countries now use polymer notes. This new substrate, paired with advanced security features has made Canadian banknotes one of most secure in the world.
While the percentage of counterfeit notes in circulation remains small, advances in technology have brought about an increase in computer generated counterfeit notes. Not only Harriet is in good company, but also she is in good hands.
Even though kids can’t vote, they can really make a difference – just ask Harriet Tubman.
Note: the idea for this post came from Mina I. Shaw, a fifth grade elementary student in New Jersey. She wrote the opening paragraphs (edited) about the life of Harriet Tabman. She is Sina Ebnesajjad’s granddaughter.
All opinions shared in this post are the author’s own.
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Dr. Sina Ebnesajjad
President at FluoroConsultants Group, LLC
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