By Cassandra Balentine
Secure printing encompasses a range of applications from identity cards to bank notes, checks, and stamps. This article discusses how vision/inspection systems combat counterfeiting and/or smuggling.
Securing Important Prints
Security printers rely on the use of advanced inspection systems to verify the accuracy and quality of the anti-counterfeiting features in their products.
“These high-level inspection systems are equipped with capabilities that exceed what is required for typical label or packaging production. These systems utilize unique inspection algorithms developed for each type of security feature, often require very high-resolution cameras, and use special lighting units and other proprietary techniques. Companies that provide inspection solutions for security print must be nimble and able to make frequent improvements to their systems to meet the ever changing needs of the security printer and market requirements,” comments Gerry Stanford, global sales leader, security print, Baldwin Vision Systems.
When it comes to highly sensitive applications, Yashashree Potdar, workflow solutions analyst, Standard Finishing Systems, agrees, adding that inspection systems monitor the smallest details on each and every page across the entire job and are essential to ensure compliance.
“Modern inspection systems can perform verification on virtually any standard symbology, including one and two dimensional code, optical character recognition characters, MICR, addresses, or even optical mark recognition at the click of a mouse or via touchscreen. Many of these systems can also prevent costly waste by identifying defects early in the production process. Some systems can even automatically pause production for extreme defects,” she explains.
Inspection systems can combat counterfeiting by ensuring total accuracy on all printed items. “The system will check for errors in critical text, as well as graphical components including specific colors and barcodes. By ensuring that legitimate printed materials are error-free and their unique elements are accurate—like colors and barcodes—counterfeit products are easily identified,” notes Julie Meredith, head of marketing, GlobalVision.
“Genuine and legitimate documents and products exhibit distinct quality features by which they distinguish themselves from fakes,” shares Jochen Kirsch, sales director, business unit security, ISRA VISION GmbH. For this to be warranted, optical security features on banknotes, passports, identification cards, stamps, and brand protection stickers must stay at least one step ahead of what counterfeiters can fabricate. He says automated, optical inline inspection systems monitoring production processes are indispensable in sustaining the rigorous quality standards of the industry. “In the field, optical inspection solutions help verifying authenticity features that lie beyond the capabilities of the human eye.”
Stanford sees a variety of special product features used to prevent counterfeiting. These start with the use of special paper, polymer, or hybrid substrates manufactured with embedded or applied security features before the printing process. A few examples include security threads, fluorescent fibers, and coatings.
“During print and production, many additional overt and covert features are added depending on the level of security required by the final product. These can include multiple methods of overlaying print, watermarks, microprint, UV fluorescent print, infrared reflective, absorbent inks, holograms, and other optically variable devices, additional coatings and varnishes, overt and covert serial numbers, and barcodes,” he says.
These security features are often combined in ways that multiply the security of the final product. “By design, all of these features are difficult to produce so are therefore difficult to copy. Many features are difficult to see due to size or application, and in the case of covert features, can only be seen with the use of special wavelengths of light,” adds Stanford.
Security inks are commonly used for banknotes, passports, and sports tickets, etc., as an anti-counterfeit measure. Security inks reflect certain near infrared (NIR) wavelengths and can be readily verified using vision technology,” adds Xing-Fei He, senior product manager, Teledyne DALSA.
Keeping an Audit Trail
In certain applications, maintaining an audit trail is important throughout a product’s lifecycle.
Advanced inspection solutions can collect the process and product data from each of the multiple inspection systems required in a typical security print process. “This data and a secure audit trail is provided to the printer for review and to feed into a post-print tracking process. Track and trace solutions can be used to continue the data tracking of secure products after the printing process,” explains Stanford.
Security and audit trails are an integral part of compliance and data integrity best practices in regulated industries. “For example, pharmaceutical companies, as well as print and packaging companies that serve the pharmaceutical industry need to meet FDA 21 CFR Part 11 compliance for products being sold in the U.S., as well as Annex 11 compliance for products being sold in Europe,” says Meredith.
Automated inspection systems work hand-in-hand with material tracking system solutions for total control and transparency of the entire production process chain. The European Central Bank for instance demands such end-to-end monitoring to be in place for all processes involved in the manufacturing of Euro banknotes, comments Kirsch.
For the security application industry and for any shop that produces applications with sensitive information, Potdar says audit trails are essential for data compliance. Most modern inspection systems come with tracking built in.
The Hunkeler WI8 System together with Hunkeler Site Manager provides complete tracking of all documents inspected by the WI8. Reports can then be exported on Site Manager. There are also tracking systems for Horizon finishing machines that can perform book block cover matching and verify correct page order—helpful for variable financial and insurance information booklets and statements. “These systems can also be used to complete the required audit trail of package assembly for the production of documents with personal and sensitive information,” says Potter.
ISRA VISION partners with Zeiser Inspectron to offer paper mills and print shops fully networked quality assurance and material tracking solutions that exchange data in real time and produce auditable process documentation.
“Inspection systems that support compliance are an absolute must-have for regulated industries,” says Meredith. When these companies are audited by regulatory agencies such as the FDA, audit trails allow for full traceability and ultimately a smoother experience for quality teams.
Additionally, she explains that audit trails are a key way to keep system users accountable for their activities while providing managers with 100 percent visibility of documents and activities. Comprehensive reports also get stored in audit trails, which are a compilation of the output of all inspections performed by the system.
Electronic signatures is also a complimentary feature to support audit trails and data integrity, allowing users and system administrators to sign off on reports with a unique signature and time and date stamp, providing an additional layer of security and traceability, adds Meredith.
Beyond the security printing industry, vision/inspection systems provide security and/or anti-counterfeiting to printed documents like labels and packaging.
In the traditional label and packaging market, Stanford points out that the use of security features is growing. Products such as brand protection labels and pharmaceutical packaging now often utilize secure features including holograms, covert ink features and numbering, and special codes. “The inspection to verify accuracy and quality of these features in label and packaging presents the same challenges and requires the same advanced inspection systems as used in security print.”
The same technology that works well for security printing does wonders for commercial printing, given that the latter usually has considerably lower levels of complexity. “Digital printing presents automated optical inspection with new challenges in both commercial and security printing,” says Kirsch.
Inspection systems are used to perform automated inspections on packaging components such as labels, cartons, and inserts at the final stages of their creation process. “Typically, printers use these systems to ensure total accuracy in text, graphics, colors, and barcodes by comparing the error-free ‘master file’ to the ‘prepress file’ prior to printing,” comments Meredith.
As a second layer of security, Meredith says the printers send their final proofs to the brands where the incoming brand’s quality team will then use an inspection system to compare the printer’s proof to their FDA-approved version.
In workflows where the printer and the brand company both utilize automated inspection systems, Meredith feels that there is virtually no room for human error to be introduced, and the packaging components can go to market error-free—preventing the risk of recalls, customer complaints, or regulatory sanctions.
Vision-based technology such as color or multispectral imaging is used for 100 percent inspection on the quality of inks after each printing process.
He says traditionally, color imaging is used for printing inspection. Separately, an additional NIR imaging system is added to the system when required.
Stanford agrees, pointing out that some pharmaceutical and security printers use inspection systems at multiple points in the overall production process.
These systems can be integrated either inline or offline. “For example, the Hunkeler WI8 System can be used as a standalone system before an unwinder, integrated into Hunkeler solutions on the finishing end, or it can even be integrated into the press itself,” says Potdar.
At a minimum, print inspection systems are integrated onto the press soon after the final print stage so any quality problems will be identified quickly and while the ability to make changes still exists. “Any defects found on press can be data mapped and removed at a separate post-press defect removal process,” shares Stanford.
Some printers prefer to inspect their products in an offline process after printing. Stanford feels there are many reasons for this including the ability to run the output of multiple presses into fewer offline inspection machines, or the requirement to inspect the product after any post-press converting and/or handling where non-print defects could occur.
Automated optical inspection systems monitor all processes without exception. “For instance, in the production of holographic stickers for brand protection there are specific inline vision systems for embossing, printing, metallization, de-metallization, die cutting, thread slitting and the final quality gate,” comments Kirsch.
Technologies like artificial intelligence (AI) are integrated into vision/inspection systems.
Stanford points out that the Baldwin Guardian PQV inspection system features a unique automatic learning capability that provides the ability to learn non-critical defects without reducing the inspection sensitivity and effectiveness of the entire sheet or repeat.
Machine learning has played an increasingly important role in machine vision in recent years, and AI is expected to become an even more powerful factor in the future. “Inspection challenges are becoming increasingly complex. Highly involved and intentionally variable optical appearances are where conventional technology comes to its limits and AI opens up new possibilities,” offers Kirsch.
New technologies such as AI are being integrated into inspection systems by creating rule-based algorithms, enabling users to perform even faster and more thorough automated quality checks, whether they are inspecting securities or packaging components, points out Meredith.
Vision/Inspection for Security
Vision and inspection systems are important for secure production of items like identity cards and stamps. It is also utilized for tracking and tracing high-value items and thwarting counterfeiting and smuggling.
Apr2023, DPS Magazine