Corrugated boxes have been in wide use for over a century. In fact they are the most used form of transport packaging (95% of North American consumer goods are transported around the globe in corrugated boxes). They are not only used to transport products domestically and internationally, but also used to display and promote retail products (Point of Purchase or POP displays).
Corrugated boxes are also increasingly being used as primary packaging in lieu of traditional folding cartons.
Corrugated is used in almost every facet and genre of consumer goods:
- food and beverage
- office supplies
- books
- electronics
- clothing
- building materials/tools
- etc.
There are well over 1000 facilities in the United States that either manufacture or convert corrugated, or both.
What are Corrugated Boxes?
Corrugated boxes (known also as “combined board“, “corrugated fiberboard“, or “corrugated board“) are composed of two main elements:
Both of these elements are made from the same type of robust paper called containerboard.
- Medium – the center fluted (corrugated) material, sometimes called “corrugated medium”
- Linerboard – the flat outside sheets of paper that are glued to the medium
So, take a flat sheet of containerboard and put waves in it (commonly called “flutes”). Then glue this fluted paper (now referred to as the “medium”) to one or more pieces of another flat sheet of containerboard referred to as “linerboard”. What you get is called “combined board”. Combined board is very strong relative to its cost and is very recyclable (in fact, it is recycled more than all other packaging materials).
The Medium of Corrugated Boxes have 5 basic “flute classifications” also called “flute profiles”:
A Flute: is the original flute size with approximately 33 flutes (waves) per foot.
B Flute: has smaller flutes than A Flute and has more of them, around 47 flutes per foot. It was created to box canned goods that were self-supporting and thus didn’t require as much load support.
C Flute: was invented next to serve as an all-purpose size and has about 38 flutes per foot.
E Flute: is thinner with 90 flutes per foot
F Flute: was created to be used as a folding carton would be – to hold light to medium-weight retail goods and be printed on either directly or using a litho laminated label.
* It’s important to note that flute profiles are more like guidelines and can vary among manufacturers in regards to size of actual flutes and amount of flutes per foot. Also to note, there exist many more flute profiles than the 5 basic ones I listed above.
So typically, the larger the flute size, the more cushioning and compression resistance it offers. Smaller flutes offer better graphics printing capabilities. The smallest flute sizes like E and F can be used instead of standard folding carton boxes (primary retail boxes) and can offer greater strength and structural integrity as well. Here is an image of a corrugated box used as primary retail packaging. The graphics look great.
There are Four Basic Kinds of Combined Board:
- Single Face – a corrugated medium and a single sheet of linerboard are glued together
- Single Wall (Double Face) – a corrugated medium and two sheets of liner board (one on each side) are glued together
- Double Wall – three sheets of linerboard are glued to two mediums
- Triple Wall – four sheets of linerboard are glued to three mediums
It’s not uncommon for different flute profiles to be used in the same piece of combined board. For example, a triple wall board may have a layer of A flute medium combined with a layer of C flute and E flute. Having multiple flute profiles varies the packaging’s compression and cushioning, as well as overall thickness and printability to suite the customer’s needs.
When buying corrugated packaging, it is important to let your supplier know the purpose and weight of the product going inside, the marketing needs of the packaging’s exterior, when you need the packaging completed, and how it will ultimately be transported. The supplier will then be able to take this information and make custom corrugated packaging for you in a timely manner that should cost you the least amount of money, and at the same time, keep your product safe from damage.
This has been a part of my tutorial series called How to Buy Packaging 101. So click the link below to head back if you haven’t finished reading it yet. 🙂
4 Responses
Does corrugated cardboards have different thicknesses.. like 5 mm, 3 mm.. is there a common thickness that is used?
also if I want more strength should I specify more thickness or specify double/triple wall or both? I am buying from China and want to make sure I buy cartoons that are strong enough.
Thx
Fadi
Hi Fadi, yes – corrugated boxes do have different thicknesses. Here in the US we go by fluting, thinnest being F flute and up to B/C. They do have corresponding thicknesses to what China provides and there are lots of conversion charts our there via Google. I would not suggest anything to your manufacturer because that puts the liability on you and incase anything goes wrong they will not take any blame. As it is, its hard gain any recourse when dealing with China. What I do suggest is to ask your manufacturer rep for suggestions to resolve your problem or the end goal. Show them evidence of either pictures or actual samples so they can see what is occurring and that you need it to be addressed and corrected. I would also recommend you try some type of testing method to ensure they will follow the successful method moving forward. Even make up a “requirements” list they have to go by or refuse their product before you unload – this may be in an extreme excessive thing to do but it does tell your manufacturer that you are serious about addressing the problem. As them for samples of what is available either by photos or actually sending you samples too.
Hi Sara,
How does one go by choosing the correct packaging for a knock down furniture product? How do i decide on the thickness of the board? How do i know the weight restriction? What wall should i use?
Look forward to hearing from you.
Hi Taran, I suggest hiring a structural engineer (with a company or independently) to have your questions answered. When you receive the dielines and material selections, quote with companies only that have testing capabilities. During the prototyping phase, they will test and adjust materials accordingly. Companies with testing capabilities also know the freight requirements and can also suggest pallet configurations. I only suggest hiring a structural engineer when typically its free, is because then you are not locked into one specific company and can shop it around.