Introduction
Have you ever looked at a pouch or film and spotted faint “waves” or unwanted patterns in the print? That’s not just a visual glitch — it’s often the dreaded moiré effect in flexographic printing. For CPG brands, it means weaker shelf impact, off-brand colour rendering, and escalating print costs.
In this guide, we’ll explain what moiré is, how modern screening (including stochastic/FM screening and advanced CDI/plate systems) solves it, and what questions you should ask when evaluating a flexible packaging converter. With the right knowledge, you’ll turn print quality into a strategic advantage.
What is Moiré in Flexographic Printing?
Moiré (definition): an unintended pattern or “ripple” effect caused by interference between halftone screen dots and colour separations.
Why it matters: On flexible pouches and films, moiré can degrade photo realism, brand colour consistency, and elevate run rejects or re-runs.
Common causes: improper screen angles; conflicting dot grids; mechanical misalignment; low-resolution plates or anilox mis-match.
Conventional vs. Stochastic (FM) Screening — The Big Difference
Conventional screening (AM): uses fixed dot grids and regularly spaced halftone dots. Prone to moiré when screen angles clash.
Stochastic (FM) screening: uses random dot placement, smaller dot size, eliminates interference patterns and significantly reduces moiré risk.
Table of comparison:
Feature
Conventional (AM)
Stochastic (FM)
Dot placement
Regular grid
Randomised
Moiré risk
Higher
Much lower
Print quality
Good
Premium, especially for expanded gamut or photo-intense art
Prepress/plate demands
Moderate
Higher (requires fingerprinting, tighter control)
How Advanced Plate/Screening Technology Solves Moiré (and Boosts Shelf Impact)
Converter must invest in high-resolution CDIs and plates capable of ultra-fine detail.
Screening strategy: selecting correct screen angles (for example, 30° difference between CMK, Yellow at 15°) and matching anilox/plate line counts prevents the pattern maths that causes moiré.
Pre-press “fingerprints”: testing dot gain, substrate behaviour, and adjusting screening accordingly ensures repeatable quality.
Benefits for you: more accurate brand colour, stronger photo/graphic reproduction, fewer rejects or customer complaints, fewer repeats — and value justification for premium packaging runs.
What to Ask Your Converter
“Do you use stochastic (FM) screening or hybrid screening for my job?”
“What CDI/plate systems are you running? (e.g., Esko Quartz, exposure resolution)?”
“Can you show me a print-run example that eliminated moiré on a similar substrate/art?”
“What are your screening angles and anilox/plate line count ratios for this job?”
“How do you handle expanded-gamut or hi-photo comprehensive art?”
“What is your rejection or customer-complaint rate for moiré or screening defects?”
Providing you ask these, you’ll shift from being a run-order to being a partner in achieving print excellence.
FAQ
Q1: Can moiré ever be entirely eliminated?
A1: Yes — with the right screening (FM/stochastic), optimized plates and prepress procedures, moiré risk can be reduced to near-zero. The key is controlling the dot interactions before press.
Q2: Does FM screening cost more?
A2: Typically yes — more demanding plate imaging, more rigorous fingerprinting and process control. But the ROI comes through fewer re-runs, higher first-pass quality and stronger shelf impact.
Q3: My converter says “we don’t see moiré” — should I still care?
A3: Absolutely. Moiré may begin subtly (e.g., on large solid colour areas or transitional gradients) and may not cause immediate failure. A job vulnerable to it still undermines brand premium. Ask for their screening strategy and sample prints.
Conclusion
Moiré isn’t just a nuisance — for CPG brands, it’s a hidden cost factoring into compromised shelf impact, increased print risk and brand equity degradation. By understanding the screening methods (conventional vs stochastic), evaluating your converter’s tech stack and asking the right questions, you turn print quality into a strategic advantage.
At Admiral Packaging, we’re built to absorb disruption — Let’s talk about how we can provide your next flexible packaging SKU with moiré-free precision, shelf-winning visuals and first-pass success.
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