What kind of filter cotton invoice does it belong to? Filter cotton belongs to group 2204, category 22 of trademark classification, and the range of filter cotton is relatively wide. Filter cotton (filter screen) usually refers to air filtration. According to different materials, filter materials are divided into four types: synthetic fiber filter cotton, non-woven filter cotton, glass fiber filter cotton and activated carbon filter cotton. Filter cotton can also be divided into primary filter cotton and intermediate filter cotton according to the different filtration efficiency, so there are still many types of filter cotton. It depends on your own choice. If you want to use that type, buy the filter cotton that suits you best, that is, a variety of types.