GRADE COMPARISON
SBS Board vs Duplex Board: Which One for Your Cartons?
When a converter asks us for carton board, the choice usually sits between SBS and duplex. They are not interchangeable, and the price gap between them is wide enough that picking the wrong one is costly in either direction.
SBS in one paragraph
SBS stands for solid bleached sulphate. It is made entirely from bleached chemical pulp, so it is white all the way through, not just on the surface. Most SBS carries a mineral or synthetic coating on the top face — C1S, coated one side — and often on the reverse as well, C2S.
The result is a clean, bright, consistent board that prints extremely well and carries no recycled content.
Duplex in one paragraph
Duplex board is built in layers, typically with a white or coated top liner over a grey or brown recycled back. It is cheaper per tonne because the core is recycled fibre.
It prints acceptably on the coated face. The back stays visibly grey, which is fine for the majority of cartons where nobody looks inside.
Side by side
| SBS | Duplex | |
|---|---|---|
| Composition | Virgin bleached pulp throughout | Coated liner over recycled core |
| Back surface | White | Grey or brown |
| Print quality | Excellent, high fidelity | Good on the coated face |
| Stiffness per GSM | Higher | Lower |
| Food contact | Suitable | Depends on grade and barrier |
| Relative cost | Higher | Lower |
| Typical GSM | 170 – 400 | 200 – 450 |
When SBS earns its price
Food contact. Virgin fibre with no recycled content is the straightforward answer to direct food packaging. Recycled cores can carry mineral oil residues, which is why regulators and brand owners are cautious about them.
Premium retail. Cosmetics, pharmaceuticals, confectionery — anywhere the carton is part of the product experience. A white interior reads as quality the moment the box is opened.
Fine print work. Small type, fine screens, metallics and heavy ink coverage all reproduce better on a coated SBS surface.
Stiffness at lower weight. Because SBS is stiffer per GSM, you can sometimes drop to a lighter board and keep the same carton rigidity, which claws back part of the cost difference.
When duplex is the sensible choice
Most cartons do not need SBS. If the box holds a sealed inner pack, if the back is never seen, if the print is one or two colours — duplex does the job at a materially lower cost.
Hardware, dry goods, bulk retail, shelf-ready packaging for non-food lines: duplex is the default, and paying for SBS there is money spent on nothing the customer notices.
The question to ask first
Does anything about this carton require virgin fibre or a white interior?
If yes, specify SBS and decide between C1S and C2S based on whether the reverse needs printing. If no, duplex almost certainly works, and the saving is best spent on a heavier grade or better print.
We supply SBS board in reels and sheets. Tell us the GSM, finish and quantity you need and we will confirm availability and pricing.
WHERE IT ENDS UP
Board in production
