According to an article in JakartaGlobe dated 13 August 2011, Bank Indonesia is planning to upgrade the security of its banknotes with a new series to be printed by October at the latest. The new notes will feature “rainbow printing,” which allows several colors to be printed using a single plate in specially modified equipment, resulting in a natural blending of the colors that is difficult to reproduce using commercially available printers. The only Indonesian note to currently feature rainbow printing is the 10,000-rupiah note dated 2010, shown above.
“Now we will also use rainbow printing for the Rp 20,000, Rp 50,000 and Rp 100,000 bills. This is in line with international standards,” said Muhammad Dahlan, the central bank’s director for circulation.