Filter paper can generally be divided into qualitative and quantitative two. In the application of analytical chemistry, the residue collected on the filter paper after inorganic compounds are separated by filtration can be used as a calculation of the churn rate during the experiment. Qualitative filter paper has more cotton fiber after filtration, so it is only suitable for qualitative analysis; quantitative filter paper, especially ashless filter paper, can resist chemical reaction more effectively by special processing procedures, so the generated Less impurities can be used for quantitative analysis. In addition to the filter paper used in general laboratory applications, there are many filter paper applications in life and engineering. Coffee filter paper is one of the most widely used filter papers. The filter paper on the outer layer of the tea bag provides high softness and high wet strength. Other air filter papers that use suspended particles in test air, and fiber filter papers for different industrial applications.