Best: Automation with Inline Spectrophotometers
Imagine taking all the benefits we have outlined in this article regarding the switch from densitometers to spectrophotometers, plus the benefits of using color quality software, and coupling them together with an automated color measurement system that is integrated directly inside the press.
Inline color measurement systems exist today for packaging printers and can be retrofitted to your existing press. Also, these systems are much more affordable than you might think and offer an easy ROI if you take a close look. While some utilize cameras to synthesize color measurements, true spectrophotometer-based systems are available and offer excellent agreement with handheld instruments. These systems can be used during makeready or at full production press speeds, and by eliminating the need to stop the press, cut out samples, and take measurements by hand, productivity is greatly increased for press operators.
Finally, with automated systems, color measurements occur more frequently and more regularly, which can further ensure adherence to the job specifications.
Building on the job-based workflow of color quality solutions, inline measurement systems allow specific measurement locations to be defined either ahead of time (in prepress) or by the press operator at run time.
During makeready, when the operator is adjusting the color on press, these systems have a measurement mode that constantly and repeatedly measures the color locations in the job and reports the data back in real-time. This allows operators to see the effect of color adjustments and know immediately when the tolerances have been met for the job, which greatly reduces wasted materials and makeready times. Then, once the press is up to color and in “production,” the measurement frequency of inline systems is typically reduced by the operator, based on either the number of impressions or the length of material printed.
“Best” Benefits
And once more, there are associated benefits:
- Inline measurement systems can greatly reduce press makereadies, which reduces wasted materials and frees up valuable press time
- Automation ensures that color measurements occur regularly throughout the entire pressrun and eliminates the measurement burden for the operator
- While color on a flexographic press tends to shift over time, due to changes with ink viscosities, anilox rolls, doctor blades, etc., with more frequent color measurements, inline systems are predictive and can detect when color begins to drift, alerting operators to take corrective action before color goes out of tolerance
- Inline systems have the ability to traverse across the entire web width, measure color bars on both the “operator” and “gear” sides of the web, and display measurement data independently for each side of the press to ensure uniform color
- Because inline systems can move across the web, some offer the ability to measure color directly from in-image locations (in addition to operator- and gear-side color bars)
- Live web viewing and bar code grading are also features on inline solutions which extend their value beyond just automated color measurements. Monitoring registration and bar code readability in real-time can further reduce waste and save printers money
- Inline solutions have the ability to provide CPGCs many more color measurements during the pressrun without stopping
“Score card systems are typically included in color quality solutions and allow individual print metrics to be weighted, scored, and rolled up into a single pass/fail number that can be used to more easily assess the color quality of the job.”
Final Thoughts
The trends are clear. Brand owners will continue to place ever increasing demands for color accuracy and color consistency on their print supply chain. For packaging printers, achieving these requirements is not only challenging—It can also mean turning away or losing business if existing processes are not able to achieve these tighter color quality specifications.
Newer technologies available today help us measure color more efficiently, remove the color guesswork for our operators, reduce makeready times, improve color accuracy and consistency, and transform print production environments so they are highly reliable, and most importantly, more profitable.
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