Paper is the preferable substance in regards to environment-friendly products. Now a day, we can find different kinds of paper with a distinct degree of durability and depth. The usage of paper is not at all limited to authorship anymore. This may now range from some personal hygiene items to packaging kinds of stuff. Wax packaging, seafood packaging, and the poultry boxes are fully made up of this paper. With its many uses, this is quite interesting to know how the papers are made.
Paper making is considered to be a non-food application for starches globally, by consuming millions of metric tons annually. For instance, in the typical sheet of copy paper contains more than 8 percent of starch in it. In paper making, there are many parts and while it comes to the wet part of the paper making process, cationic starches that have the positive charge bound to the starch polymer are used.
There are various varieties of paper in existence. They are:
- Printing papers
- Drawing papers
- Writing papers
- Blotting papers
- Handmade papers
- Wrapping papers
- Specialty papers
- Wood pulp paper
- Cotton paper
- Wood-free paper
- Tree-free paper
- Acid-free paper
The cationic starch with some other retention and also with sizing agents can help you to give necessary strength properties to paper formed in the paper making process to the final paper sheet. In that, the sizing agent plays a major role. As like another sizing of other components, the paper also comes across sizing agents in order to provide perfect size to paper.
Like Textile sizing chemical, for paper manufacturing we are using the sizing agents can be taken in various phases. While comes to paper, sizing is used during paper manufacture in order to reduce the tendency of paper when it dry to absorb the liquid, with an aim of allowing paints and inks to remain on the surface of the paper and to dry there, rather than allowing ink to absorb into the paper. This sizing agent helps to provide more economical, consistent, and precise painting, writing, and the printing surface. This can be achieved by the curbing the tendency of the paper fiber to absorb the liquid in action by capillary action. In addition to that, sizing may affect the abrasiveness, finish, smoothness, risibility, printability, and the surface bond strength and thus it decreases the surface fuzzing and the porosity.
While coming to sizing, it has three main categories. They are:
- Un-sized also was known as water leaf
- Strong sized also known as hard sized
- Weak sized also known as slack sized
The un-sized has low water resistance and this includes he absorbent paper for blotting. The hard-sized paper has high water resistance such as liquid packaging board and the coated fine paper, while the weak sized paper is somewhat an absorbent and this also includes the newsprint.
In sizing, there are two main types. They are surface sizing and internal sizing. Internal sizing is mostly applied to all type of papers and especially everything is machine made, while the surface sizing is also added for some highest grade bond and the writing paper.