What ink is used to print us currency?

"In 2010, the Bureau of Engraving and Printing in the United States printed 26 million notes… every day! They have two facilities where the notes are printed: Washington, DC and Fort Worth, TX and the average cost to produce a banknote ranges from 3-12 cents, with an average of 9.6 cents per note.

DELLe, "Helvetica Neue", Helvetica, Arial, sans-serif; font-size: 16px; background-color: rgb(255, 255, 255);"> US paper currency is designed with numerous anti-counterfeiting security features (both covert and overt), such as watermarks, micro-printing, security threads that glow under UV light, serial numbers, federal reserve markers and low vision numerals. The Security Features Development Group within the Bureau works very closely with the Secret Service and Federal Reserve Bank to design anti-counterfeiting features."