Kraft paper is paper or board made of chemical pulp usually derived from the wood pulp found in mills and plants. The chemical composition of this kind of paper is quite simple and has to pass through a series of complex processes and conditions in order to give us fine quality paper products. The most common Kraft paper are the following:
Brown paper. This is the most common Kraft paper available in shops and stores. The chemical composition of this kind of paper is quite simple, consisting of binder’s, water, lignin, cellulose, and wax. The main characteristic of this kind of Kraft paper is its natural brown color, which is acquired after the lignin is mixed with the water.
Cardboard. This kind of Kraft paper is used in factory, shops, and other places that need thick cardboard sheets. The main characteristics of this type of Kraft paper are that it contains a high amount of water content and lignin content, which give it the natural brown color. The chemical composition of this kind of Kraft paper depends on the brand, and most manufacturers use various chemicals to improve the quality of the pulp used. This type of material is most common when considering custom boxes for ecommerce or cosmetics. Some of these chemicals include potassium hydroxide, calcium carbonate, magnesium sulfate, sodium chloride, sodium lauryl sulfate, and many more.
German Kraft paper. This type of Kraft paper is made by using a brand of pulp consisting of wheat, rye, oats, or corn, along with a certain amount of other ingredients. The main qualities of this type of Kraft paper are its strength, color, and texture.
Unbleached Kraft paper. The main characteristic of unbleached Kraft paper is that it does not contain any bleaching agent, which makes it more stain resistant. However, unbleached pulp does not last long, thus, they are often thrown away after usage.
Sacked Kraft paper. Similar to the unbleached variety, bagged Kraft paper has no bleaching agent. This makes it a popular choice among printer manufacturers who want paper with the least amount of chemicals to ensure its strength. However, the bagged variety does not have the same strength as the unbleached variety, thus, the manufacturers often add bleaching agents to the bags to increase the strength of the final product.
Brown paper. Brown Kraft paper is made from recycled pulp that is left after the cutting and milling processes. The resulting material is soft, thick, and strong. Since most printer manufacturers prefer this type of Kraft paper, they often request suppliers to provide them with bags or sacks in order to produce their products.
Bleach-free Kraft paper. In addition to the regular bleaching process described above, this type of packaging is also bleached using chemicals that are safe for human consumption. This process, called ionization, produces colors that are similar to those of regular Kraft paper. This bleaching method protects the cardboard from any damage, which means that the end product will be free of defects. Moreover, by using bleaches, manufacturers reduce their production costs since the finished products will be more pure and free of blemishes.