Raw materials and classification of paper：
The raw materials of paper mainly include plant fibers, such as wood, bamboo, reed and so on.
In order to improve the performance of the paper, auxiliary ingredients such as fillers, adhesives and colors are also added.
Fillers such as talc, kaolin and barium sulfate, colloids such as rosin, alum and starch, colors such as inorganic pigments and organic dyes .
Paper can be divided into the following categories by use:
cultural paper : used for writing, printing and publishing, such as newsprint, writing paper, offset paper and so on.
wrapping paper : used for commodity packaging, such as kraft paper, corrugated paper and so on.
household paper : such as toilet paper, paper towels, etc.
special paper : with special purposes, such as filter paper, insulating paper.