Material Summary – Kraft Paper

What is Kraft paper? #

Kraft paper, also known as kraft, is a type of paper made from wood pulp that has been processed using the Kraft process. This process involves the use of chemicals, such as sodium hydroxide and sodium sulfate, to break down the wood fibers and create a strong, durable paper.

How is Kraft paper made? #

The first step in the Kraft process is to prepare the wood chips, which are typically obtained from trees that have been sustainably harvested. The wood chips are washed and screened to remove impurities and then soaked in a solution of sodium hydroxide and sodium sulfate, which breaks down the lignin in the wood fibers and softens the chips.

Next, the softened wood chips are mechanically crushed and ground to release the fibers. This is typically done using a refiner, which is a machine that uses high-pressure steam and blades to break the chips into fibers. The fibers are then screened and washed to remove any remaining chemicals and impurities.

The resulting wood pulp is then ready to be used to make kraft paper. The pulp is mixed with water to create a slurry, which is then formed into sheets of paper using a machine called a Fourdrinier. This machine uses a moving mesh of wires to create a continuous sheet of paper, which is then pressed and dried to remove the water and create the final product.

How is Kraft paper used in food packaging? #

Kraft paper is commonly used in food packaging due to its strong, moisture-resistant properties, which help to protect the food from damage and extend its shelf life. It is often used to make bags and wrappers for a variety of foods, including snacks, candy, and baked goods.

One of the key differences between kraft paper and other types of paper used in food packaging is the barrier liner. This is a layer of material, such as wax or plastic, that is applied to the inside of the kraft paper to provide additional protection against moisture and other elements. Different types of barrier liners offer varying levels of protection, so it’s important to choose the right liner for the specific type of food being packaged.

Is Kraft paper eco-friendly? #

Eco-friendly pundits often choose kraft paper over recyclable plastic for food packaging because it offers several environmental benefits. As a renewable and biodegradable material, kraft paper can be composted or recycled, which reduces its impact on the environment compared to plastic.

In addition, the production of kraft paper requires less water than plastic, which is a scarce and valuable resource. The manufacturing process for kraft paper involves the use of water to break down the wood fibers and create the paper, but this water is typically recycled and reused in the process. In contrast, the production of plastic requires the use of large amounts of water, which can be difficult and expensive to recycle.

Furthermore, the disposal of kraft paper has a lower impact on the environment compared to plastic. When kraft paper is disposed of in a landfill, it will break down and biodegrade over time, whereas plastic will remain intact and potentially release harmful chemicals into the ground and water.

Conclusion #

Overall, using kraft paper for food packaging offers several benefits compared to plastic, including its renewability, biodegradability, and lower water use. While it may not provide the same level of protection as plastic, it can be a more sustainable and eco-friendly option for packaging food products.