Intaglio – Secure Print Technology

By Robert Sherwood, CPP

People interact with intaglio print every day, but few realize when handling currency, they are experiencing the unique look and feel of the technology. I was first introduced to the intaglio printing process when I attended art school creating handmade images. Intaglio hand-operated presses produce limited print editions and found in most art schools, but the number of commercial and government presses is extremely small compared to technologies such as offset, flexography, and screen printing.

What is Intaglio Printing

Intaglio is a print technology using an engraved plate, special inks, pressure, and heat depositing a raised print on the surface of the substrate. Intaglio’s unique qualities provide overt, semi-covert, and forensic features distinguished from all other print technologies.

A Short History of Intaglio Printing

Intaglio may have originated by artisans in the mid-1400s utilizing engraving to decorate metalwork such as armor or musical instruments. Making prints of their work may have been a method to create a record of the engravings. By the late 1400s, artists such as Albrecht Durer began to use intaglio as their medium. By the nineteenth-century chemical, etching was introduced, expanding imaging potential. By the 1940s, the development of multi-color presses moved intaglio into the high-technology space, improving artistic options and increasing security. At one time intaglio was widely used to print banknotes, stocks and bonds, wallpaper, sheet music, maps, and other mass-produced materials. Today, the few remaining intaglio printing operations are owned by governments or businesses concentrating on printing passports, visas, vital records, stamps, and other security products.

 How Intaglio Printing Works

Intaglio print utilizes a plate, usually made of copper or nickel. The lines are engraved or etched into the plate and filled with ink. Plate surfaces are cleaned, and the ink is transferred to the substrate using high pressure between 3000 and 6000 Lbs/Sq/In. The deposited ink creates a raise printed surface from zero to three-thousand-inch-high, giving the print its unique tactile feel. Inks are quickly dried, passing through an oven of 400 F to 600 F. The combination of very fine detail and raised print is unique to the process.

The Security of Intaglio Printing

Intaglio has become ubiquitous as a security feature for the currencies of the world. Other applications include vital records, visas, passport, tax stamps, and anticounterfeit labels. The printing of stocks, bonds, and other security papers supported the intaglio printers until 1971, when electronic security trading replaced physical documents, and new, less expensive authentication technologies became available. Today, other technologies like gravure, offset, and flexography has replaced many former intaglio applications. 

Intaglio printers almost exclusively print identity and revenue products for governments. These printers are known and monitored by government agencies like the United States Secret Service to combat counterfeiting. There are only three commercial intaglio printers in the United States. Intaglio press manufacturers only sell to known secure entities. This exclusivity and lack of availability significantly contribute to the security of the technology.

Intaglio print encompasses three main security features exclusive to the technology:

-         Fine raised print providing tactility

-         Raised Micro text – both positive and negative formats

-         Latent images – a semi-covert image hidden in an interference pattern that appears when the printed surface is tipped into the light.  Intaglio is the only printed technology that can achieve this type of image.

The design, tooling, and printing of the intaglio process require specialized knowledge, talent, and equipment. Many processes have become proprietary or trade secrets. The combination of intaglio characteristics, unique technology, knowledge, limited availability, and government monitoring contribute to the security intaglio provides.

Leveraging Intaglio Print for Brand Protection

Counterfeiters producing and selling fake products focus most of their attention on the labeling and packaging to fool the consumer. Successful brand protection programs are built on a multi-level approach utilizing physical and software technologies, investigation, and legal actions.  

Intaglio, as part of the physical label and packaging security, allows for the “first step” of the authentication process. The differences of intaglio print compared to any other print technology is easy to determine with basic instruction and examination. Currency provides a baseline comparison for authentication of an intaglio printed label.  Minimal magnification will provide positive proof of unique intaglio characteristics. As authentication software systems utilizing smartphones expands, the physical presence of intaglio becomes critical when internet connectivity or the correct interface app is not available. Lastly, if traditional intaglio design is incorporated, the appearance of an official document projects the confidence of authenticity.

Robert Sherwood is VP of Security Programs Management at VeriTrace, Inc., a security technology company supplying anti-counterfeit labels, tapes, documents, tax stamps, visas, and other printed security products.