As per the increasing dependency on paper, it has become a crucial part of our daily activities. From reading, writing, cover applications, and packaging we are dependent on paper in many ways for many years from now. No one can deny their key importance in our life. The widest use of paper is in written communication.
Wood pulp or plant fiber is the prime raw material for paper industry. Paper manufacturing takes place under modern factories or with some hand methods. A complete structure of the paper is made of connected fibers. You can extract this fiber from multiple sources such as cloth rags. Cellulose fiber is obtained from plants and most notably trees.
At present, paper with cloth fiber mixing is known as high-quality and strong paper. Most of the paper and packaging companies are highly producing the cotton mix excellent paper for commercial uses. There are various sources of raw materials like wood, wood fiber from sawmills, recycled newspapers, and clothes, and vegetable fibers. Wood pulp is the half part of the mixture for paper construction.
The conical trees like spruce are preferred for paper making due to having long cellulose fibers. The longer is the fiber, the stronger will be the paper. Besides this, bamboo, jute fiber, flex, and cotton rag, etc also used as paper making raw material. Paper making is a very simple process. Various paper manufacturing industries follow some simple steps to manufacture industrial paper products.
Pulp Formation
Converting the huge tree logs into the crushed wood solution is known as wood pulp. There are two popular methods of pulp formation:
- Mechanical
In this process wood logs are subjected to various machines for obtaining the final product. First of all the bark removing of logs is done by tumbling them into the large drums. Then to wood down these peeled logs into fine pulp these wood logs are pressed between the huge revolving slabs and the ready pulp is filtered for removing the unwanted elements.
- Chemical
In the Chemical process, a chemical solution is used to sodium hydroxide and sodium sulfide is used to boil the debarked wood logs at high pressure in huge digesters. When these wood chips completely dissolve in the solution then the mixture is sent to a filter to separate the foreign elements.
Bleach and other coloring agents are added in this stage.
Pounding or Beating
After taking the pulp into large tubs, machine beaters are used for its appropriate beating. This is the time when filler elements like chalk, clay, and chemicals are added to it. These filler elements have a great influence on the opacity of the paper. Also some sizings like starch, resin and gums are also added to this to make the final product resistant to water-based ink.
Squeezing
In this step, a Fourdrinier machine is used to squeeze the pulp on a moving belt of fine mess screening through a series of rollers. Below the belt, there are suction devices, which drain out the water from the pulp sheet. A device named Dandy removes the watermarks if there is any. In the press section of the machine, the pulp sheet is pressed by the rollers and the remaining water is drained out through a series of heated cylinders.
Final Paper Product
The dry paper sheet is wounded on a reel and subjected to the different fillers and coatings according to the different purposes. Coatings include various pigments, chemicals, and clay. Finally, the paper sheet goes through a calendar rolling and then cuts into the appropriate sizing of pieces.
Now many trees are being specially harvested for the paper manufacturing purpose. By considering the right quantity of chemicals, fillers, and sizings a strong paper is manufactured.