Corrugated boardĀ is built from an outer liner, inner liner, and a fluted mediumĀ formed on corrugating rolls and laminated together. The flute creates an I-beamālike profile that delivers compression strength, cushioning, and impact resistanceāideal for shipping cartons, retail packs, and display packaging. Constructions include Single Wall, Double WallĀ (e.g., BC, EB), and Triple Wall, with print workflows like flexo direct print, litho-lam, and preprint.
Why Corrugated?
Strength with low weight:Ā Excellent stacking (compression)Ā and impactĀ performance at relatively low basis weight.
Cushioning:Ā Flutes absorb vibration and drops, reducing damage.
Convertibility:Ā Easy to slot, die-cut, crease, and glueācovering e-commerce boxes to premium litho-lam gift packs.
Sustainability:Ā Wood-fiber based, widely recyclable; available with FSCĀ®Ā and recycled-content options.
Flute Types & Typical Thickness
(Ranges vary by mill and regionāuse as selection guidance.)
A Flute ā Thick, Best Cushioning
Thickness:Ā ~4.5ā5.0 mm
Profile:Ā Taller flute height for strong cushioningĀ and crush recovery.
Use:Ā Fragile items, shipments needing more shock absorption.
C Flute ā Balanced, All-Purpose
Thickness:Ā ~3.5ā4.0 mm
Profile:Ā Balanced compression, cushioning, and surfaceĀ for printing.
Use:Ā Most retail/shipper cartons; common for litho-lam displays.
B Flute ā Thinner, High ECT & Better Die-Cutting
Thickness:Ā ~2.5ā3.0 mm
Profile:Ā Higher flute count per foot, flatterĀ surface; reliable stacking strength.
Use:Ā Small/medium shippers, inserts, partitions, engineered die-cuts.
E Flute ā Microflute for Premium Print
Thickness:Ā ~1.0ā1.8 mm
Profile:Ā Very smoothĀ face; sharp scores and tight foldsāgreat for high-graphicsĀ work.
Use:Ā Microflute cartonsĀ (gift/e-commerce display packs), retail trays; often replaces heavy paperboard for added strength.
F Flute ā Ultra-Micro for Fine Detail
Thickness:Ā ~0.6ā1.0 mm
Profile:Ā Extra flat; excels at fine graphicsĀ and precise folding.
Use:Ā Small luxury cartons, cosmetics, accessories, book-style boxes/inserts.
Popular Double-Wall Combinations
BC Double Wall:Ā BĀ (outside) + CĀ (inside). Strong stackingĀ plus cushioningāgood for heavier goods and long hauls.
EB Double Wall:Ā EĀ (outside) + BĀ (inside). Smooth print face with higher compressionāideal for litho-lam premium shipper/displayĀ solutions.
AB / AC:Ā Heavy-duty protection for large, fragile, or high-value products.
Selection Tips (Practical)
Weight & storage time:Ā Heavier loads or long stacking windows ā C/B/BC.
Fragility:Ā Need more shock absorption ā A/C/BC; add die-cut inserts if required.
Print & appearance:Ā High-graphics and crisp folds ā E/FĀ or EBĀ (microflute).
Logistics & cost:Ā Thinner E/FĀ improves cube efficiencyĀ and lowers freight; BCĀ boosts protection at higher material use.
Specs to check:Ā Burst, ECT/RCT, BCT, and puncture; liner (kraft/testliner) and medium basis weights drive performance.