Corrugated Cardboard
A Corrugated paperboard, or ” corrugated fiberboard or “corrugated cardboard,” is a packaging material comprising flat outer layers and a fluted inner layer. The material used in its manufacturing makes the three terms slightly different, whether crafted from paper or fibres, to provide structural strength and durability.
Regarding packaging materials, ‘cardboard’ is an umbrella term encompassing various heavy paperboards. Within this category, ‘corrugated fiberboard’ refers to a type of cardboard with a fluted layer sandwiched between flat layers. The significant structure is achieved through the corrugating process. Due to its stiffness and structural integrity, this material is ideal for shipping, retail, and storage.
Thickness of Corrugated Cardboard
The thickness of corrugated material generally depends on two of its components, which are flutes and liners.
Flutes
Fluting types measure the board callipers (thickness in inches). Each category has its own thickness and different sizing of the flutes in terms of height and frequency (the distance between the waves) of the flutes.
A Flute
This original flute design is popular because of its excellent cushioning effect and ability to be stacked on each other. Primarily, it is used for packaging fragile products and their shipment due to its strength, with 36 lines per foot and a height of ¼”.
B Flute
Type B possesses unique characteristics and features, including exceptional crushing and dent resistance. It also provides an extra layer of protection and can be used as a partition for heavier loads. With a height of ⅛” and 49 linears per foot, this type is better for packaging stability than A flute.
C Flute
The C type is another excellent option for packaging and shipping purposes because of its thickness, which is 11/64′ and 39 linears per foot. It is widely used due to its ability to withstand the rigours of handling and transportation. Moreover, it is high compression and crushing-resistant and has an ideal surface for printing and labelling.
E Flute
The E type has the subsequent crushing and bending resistance level, making it more efficient. Its relatively flat surface is suitable for smooth printing. The thin board is lightweight and ideal for high-quality printing. E flute is also a space saver because of its size. These boards are highly appreciated as an alternate option for mainstream paperboards commonly used in packaging ceramics, cosmetics, and other delicate items like glassware. Its thickness exceeds 1/16” and has 90 linears per foot.
F Flute
The F flute type is designed to package consumer goods commonly for retail. It is the thinnest among the other types, with a thickness of 1/32” and 125 linears per foot, which makes it more rigid. Less fibre is used in its making, which is why it is ideal for point-of-purchase displays, jewellery, cosmetics, and shoe boxes. It has also been used in food packaging as a clamshell container.
Each type carries the significant attributes of excellent compression, good stacking quality, robust crush resistance, and flexural rigidity.
Liner Boards
It is not only the flutes that matter but also the exterior layer, known as “flat liner boards,” which prides itself on the strength and durability of the corrugated board. These liners come in various forms, which are:
1- Kraft liners that are subcategorized based on color and their contents.
- Brown kraft liners
- White top liners
- White mottled kraft liners
- Bleached kraft liners
- Birch-faced kraft liners
2- Test liners
3- Chip liners
Types of Corrugated Cardboard
Single face
- It has two layers: a liner and a corrugated layer.
- Used to add extra cushioning.
- The order of layers is fluting-liner.
Single-Wall
- It is the most common type of corrugated cardboard.
- It consists of two outer liners and a middle layer of fluting.
- The order of layers is Liner-fluting-liner
Double-Wall
- This type is sturdy enough to be used as an alternative to wooden crates.
- Three layers of fluting combined with four layers of liners make it very strong.
- The order of layers is: liner, fluting, liner, fluting, liner, fluting, liner.
Triple-Wall
Most rolls of kraft paper are processed in corrugators to get crippled and get the perfect zigzag pattern. Then, the layers of linerboard and flutes are glued together to form various callipers or cardboard. The addition of each layer further categorizes the different types of corrugated boards.
Characteristics and Uses
Depending on the type and your preferences, this robust material can be used for a variety of packaging purposes, like:
Strength and Durability
- Corrugated fiberboard is known for its strength, making it suitable for protecting and shipping a wide range of products.
Cushioning
- The air pockets between the corrugated layers provide a cushioning effect, offering protection against shocks and impacts during transportation.
Versatility
- The fiberboards can be easily customized in size, shape, and printing, making them versatile for various packaging applications.
Sustainability
- Many corrugated fiberboards are made from recycled materials like old corrugated containers, double-lined kraft paperboards, etc, contributing to sustainability efforts in the packaging industry.
Cost-Effective
- Corrugated fiberboard is generally cost-effective compared to alternative packaging materials, and it is lightweight, making it the most demanding material worldwide.