Compare central impression and stack flexographic printing machines by register stability, substrate range, investment cost, and best-fit packaging applications.
The Core Difference
A stack flexo press uses independent printing units arranged in a stack layout, while a CI flexo press prints around one central impression drum. This architecture difference affects register stability, speed potential, footprint, cost, and substrate behavior.
When Stack Flexo Is a Better Fit
Stack flexo machines are usually selected for paper bags, nonwoven bags, woven bags, and converters that need flexible color configurations with a controlled investment. They are practical for standard packaging graphics and frequent SKU changes.
When CI Flexo Is a Better Fit
CI flexo machines are preferred for film packaging and high-speed work where color-to-color register is critical. The central impression drum supports more stable web contact, especially for flexible films.
Cost and Production Balance
A stack press is typically more cost-effective and easier to justify for entry or mid-volume production. A CI press requires a higher investment but can deliver stronger output stability and better long-run productivity.
YAOSHG Recommendation
Choose stack flexo for cost-effective multi-material work. Choose CI flexo for high-speed film, food packaging, and tighter register requirements. If job changeover and premium quality are priorities, compare servo sleeve CI and gearless full servo options.
Need help selecting a flexo press?
Send your material, web width, color count, target speed and sample packaging format. YAOSHG engineers will recommend a suitable machine series.