Sabtu, 23 Januari 2010

About "Paper"

As we all know, paper (paper) is one of widely used products. Everyday, we need papers for offices, households, schools, shops and so forth. We get the papers we need easily at bookstores, or other markets. Various types of paper such as A4 writing paper, tissue paper, newspaper, wrapping paper, paperboards, boxes, have been quite familiar with our lives. But, have we known anything and everything about the "paper"?

Technically, the various types of paper mentioned above is basically made of fibers formed into sheets with the help of additives that are added to the fiber slurry or after a sheet of paper has been made. Fiber is the largest component of paper; it ranged between 70% to 100% depending on the type of paper, while the remaining are additives of 0-30%. Various types of fiber can be used for paper, natural fibers or the virgin fibers. It is derived from wood such as pine, acacia, eucalyptus, albizzia; non-wood fibers such as rice straw, straw, baggase, hemp; and secondary or recycled fibers.

All natural fiber from wood or non-wood raw materials, previously have to be pulped first in the pulping process.Even for the making of white paper, brown pulp obtained from pulping process should be bleached in the bleaching process. In the papermaking process, additives used in general can be divided into two groups, one that serves to control the runability of the papermaking process, and that serves to establish the properties of paper. For the second type, it is including sizing agent as liquid repellent material, fillers, reinforcing agent, coating materials, dyes and so forth.

Since fiber is the largest component of the paper, the paper properties are mostly influenced by the nature of the fiber used. However, the properties of the resulting paper can be formed as needed through a variety of ways in the manufacturing process.

In addition, it is well known paperboard instead of paper. The significant difference between paper and paperboard is the basis weight or grammage. Basis weight or grammage is an important property of paper; it is used for the sale or marking of paper type. For example, a writing paper 70 means the paper basis weight is 70 grams per square meter, or abbreviated g/m2. Generally, paper has a lower basis weight of 224 g/m2, while the paperboard has a minimum basis weight of 224 g/m2. Because of this difference is paper generally thinner than paperboard. Physical differences between the paper and paperboard is the principle factor of its’ difference utility.