Paperboard is one of the most popular packaging formats in retail grocery. It's your silent salesperson, your first brand and product impression, the primary vehicle for consumer use, and it influences shopper behavior and decision making. But when you get down to the details, there are many differences from board to board. And when you talk with paperboard vendors, you'll notice significant price fluctuations and options across paperboard.

So how do we gain certainty when designing with paperboard? An educated packaging scientist understands grades of paperboard. Understanding paperboard grades is essential. Each grade features different strengths. Most importantly, grades can fluctuate in price by up to 50%. The purpose of this lecture is to introduce you to the six most common grades, their properties, and applications you'll find in the marketplace. 

So, let's get into it. 

1. SBS

Let's start with solid bleached sulfate. The word sulfate comes from the chemical used in the kraft pulping process. It's made from virgin hardwood—premium—and usually has a mineral or a synthetic coating on the top and reverse sides. It's approved for direct food contact. The best grade for surface consistency. It has the best printability, better than average diecutting and foldability, and works well in frozen applications. It's also fairly strong. SBS is sanitary and the ideal substrate to use in aromatic products like fine teas. SBS is the most expensive substrate and is widely available in North America, Canada, and Nordic countries. You'll find SBS frequently in the average US grocery market. 

2. SUS

So take those one hundred percent virgin fibers, hold the bleach, and apply a thick printable coating to one side, and you have SUS—solid unbleached sulfate. Now, this grade is popular. It's less expensive than SBS. It's the strongest of all the grades, and it's naturally resistant to moisture. And when enhanced with some coatings, it's a winner in the fridge and freezer. You'll see SUS in many applications, but most certainly as a beverage holder. You’ve got some heavy glass bottles and paperboard in a wet environment? Better use SUS. This grade goes by many names. WestRock registered the name CNK, which is coated natural kraft. It is also called CUK—coated unbleached kraft. Whatever the name, the composition is the same. 

3. UUK

So the next grade is UUK. Everything we've discussed so far—SBS and SUS—are usually made from virgin hardwood fibers, and that's expensive.

UUK is a natural grade. Both sides are brown and usually made from a blend of softwood like pine trees and hardwood. UUK may contain recycled fibers as well. The benefit of UUK is that you get a high strength at a lower cost, but if you want a crisp and bright print application, you're not gonna see that with UUK.

UUK is a popular choice for heavy duty items, hardware, and even wet environments where crisp print and high cost are not really desired. You may see a 30 to 40% discount on UUK compared to SBS, so it's worthy of your consideration. 

4. CRB

So do you need a non-food contact, versatile board with a hundred percent recycled content? Then you need some CRB—coated recycled board, a.k.a. CCN, a.k.a. CCNB, a.k.a. Duplex, a.k.a. WLC, a.k.a. GB. Phew. 

There's a lot of variation to this grade and it's fairly low strength. But if you have a low weight item like a bag of cereal, chips, or snacks, you'll find CRB an ideal choice.

5. URB

So do you have a need for a paperboard that isn't in plain view like a setup box or dividers? So a setup box would have a wrap around it and a coating. You can see there a material like that, or in terms of a divider, a material like this where you don't really see it, but it absolutely has a function for it. I mean, let's be honest, we don't wanna pay a lot for this. So URB—uncoated recycled board—is your pick by far. URB is the least expensive paperboard grade and most likely provides the highest value when you need it.

6. FBB

So I've saved the most interesting paperboard grade for last—FBB—folding box board. FBB is a multi-ply grade and is made up of one or more mechanically pulp layers leveraging strength. It's sandwiched between two layers of chemical pulp, which leverages printability, smoothness, and brightness. So it's the best of both worlds. Compared to SBS, you'll sacrifice strength, but you'll gain in usability. Depending on coatings and composition, you'll see highend FBB priced competitively with SBS and up to 35% less cost for more economical grades.

One thing about FBB that I think is cool is that it opens and closes so nicely—and you're not gonna see a lot of creasing and damage to your scores. It also makes a lot of sense if you're gonna be opening and closing a lot of things, and it can take a lot of premium enhancements. You can see the gloss on here. There's a nice emboss on this bandaid. It's engineered to be a great card.

The goal of this lecture was to raise your awareness of the most common paperboard grades, and if you're a student of the Packaging School, you'll have access to this incredibly awesome cheat sheet that summarizes everything we've talked about plus a bunch more for quick and easy reference.

Remember, packaging is a science—learn, evaluate, and test before you buy. Request samples from your vendors because they're usually free.