The Technology Behind the New $100 Bill

Bureau of Engraving and Printing's Washington, D.C., production line for the brand-new, next-generation $100 bill.
Daniel Terdiman/CNET
WASHINGTON--I'm staring at $38.4 million in cash, and it's hard not to drool.
Bureau of Engraving and Printing's Washington, D.C., production line for the brand-new, next-generation $100 bill.
Daniel Terdiman/CNET

I'm here at the U.S. Bureau of Engraving and Printing, which, as is probably best described by its official Web site, is America's "money factory."

More specifically, this is where the U.S. Treasury Department prints its paper money, and as part of Road Trip 2010, I've come here to see how the bureau makes the brand-new, next-generation $100 bill. The bureau's mission is emblazoned in red, white, and blue neon on a wall near where I came in: "We make money the old fashioned way, we PRINT it."

But jumping ahead of that process a little bit, I'll say it again: At the end of my behind-the-scenes tour, I've come face to face with two giant piles, or "skids" of perfect, clean, crisp $100s, all packaged up and ready to be shipped out, exactly 384,000 of them, and I can only shake my head and think, "what if."

That's getting ahead of myself though.

Although the bureau prints each of America's paper denominations, my tour is of the production process for the new $100, partly because it's the most advanced bill the country has ever printed, and mainly because the bureau is still in publicity mode for it. The new bill was unveiled officially on April 21.

My tour began in what is called "Offset." This, explained Offset supervisor James Sutherland, is where background color is printed on what until then had been blank sheets of the special paper the bureau uses for all our currency. That paper comes delivered with embedded purple anti-counterfeiting strips, and as well as the little colored security fibers that set our money apart, but nothing else.

Once Offset has printed the first rounds of background colors, the future $100 bills--which start as sheets of 32 bills--four across, eight down--are stacked up and set aside to dry for 72 hours. It seems a little weird to me that they dry in these large stacks, but that's how it works. After every stage in the printing process, the sheets must dry for 72 hours. And then it's on to the next stage.

We moved on to what is known as "intaglio," the section where the many elements of the new $100--the lettering, the back, the face, the seals, and more--are added.

This is also where many of the additional security--read: anti-counterfeiting--features are added. Here, that means specialty inks and color-shifting inks. I was asked not to say more, as a security precaution.

First up is the printing of the back of the bill. This is pretty straightforward, and when I come in, I talk to assistant supervisor Bob Smith, who explains what's going on. One interesting part of the process is the printing and examination of the so-called "smear sheet," which looks like a sheet of 32 $100 backs, dipped entirely in green ink. A smear sheet is printed once every 8,000 sheets or so.

A smear sheet, which is used so that printers can examine a run in order to see if anything is missing from the print.
Daniel Terdiman/CNET

The smear sheet, said Smith, is used by the printers as a way to see if everything in a run has been printed where it's supposed to be. On every sheet, the note's many authentication patterns are supposed to be in precise places, and by looking at the smear sheet, he added, the printers are able to ensure that that is the case.

But there's also automatic examination going on, Smith said. Built into the printing presses are inspection sensors that scan each sheet as it goes through, looking for defects, in a bid to "reduce spoilage." Those that the machine rejects are automatically separated "from the good work." All told, he added, about 85 percent to 90 percent of the sheets that come off the printer are deemed defect-free.

If, however, a defect is found--perhaps it's missing some print, is over-inked, under-inked, too lightly printed, or has smudges--the sheet isn't destroyed. Instead, if enough of it is salvageable, the good bills will be set aside and used as what are known as "star sheets." But more on that later.

Smith said that the bureau's printing presses have a general capacity of about 10,000 sheets an hour, but that for the new $100 bill, they're producing about 20 percent less, or about 8,000 sheets an hour. And that's because they're still in the earliest stages of the bill's production. Eventually, Smith suggested, the number will rise to normal production levels.

Read the full article at CNET.

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